Astrophysics of Galaxies
JWST Reveals Two Overmassive Black Hole Candidates in Dwarf Galaxies at z $\approx$ 0.7: Pushing Black Hole Searches into the Dwarf-Galaxy Regime
E. Iani, P. Rinaldi, A. Torralba et al. (+35 more)
We report the discovery and characterization of two compact
galaxies, Pelias and Neleus, at z ~ 0.71 and z ~ 0.75, identified in MACS J0416.1-2403 and GOODS-North. Both exhibit unusual spectral energy distributions (SEDs), with very blue rest-frame UV-optical emission and a steep rise toward near- and mid-infrared wavelengths. JWST/NIRISS and JWST/NIRSpec spectroscopy show strong rest-frame optical lines ([O III] 4959,5007 and Halpha) with extreme equivalent widths (>= 1000 Angstrom), indicating young burst-dominated populations with low
metallicities (Z ~ 0.1-0.4 Zsun), low
dust attenuation (Av ~ 0.2 mag), and
stellar masses of Mstar ~ 10^7 Msun. Nonetheless, JWST/MIRI photometry reveals a strong mid-infrared excess that cannot be explained by
stellar populations or
star-formation-heated
dust alone, requiring a hot-
dust component most naturally associated with a deeply embedded active
galactic nucleus (AGN). SED modelling yields log10(Lbol [erg/s]) ~ 43.7-44.0, implying black hole masses of log10(MBH [Msun]) ~ 5.7-6.7 under the assumption of Eddington-limited
accretion. Given the very low
stellar masses of the hosts, this corresponds to black-hole-to-
stellar mass ratios of about 6-60%, well above the extrapolation of local scaling relations. The lack of X-ray detections suggests that the
accretion may be either heavily obscured or intrinsically X-ray weak. Their SEDs also resemble those of Blue Excess Hot
Dust Obscured
Galaxies and show the characteristic V-shaped continuum seen in Little Red Dots, although with the inflection occurring at redder wavelengths.
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All authors E. Iani, P. Rinaldi, A. Torralba, J. Lyu, R. Navarro-Carrera, G. H. Rieke, F. Sun, C. Willott, Y. Zhu, A. Alonso-Herrero, M. Annunziatella, P. Bergamini, K. Caputi, M. Catone, L. Colina, R. Cooper, L. Costantin, A. Crespo Gómez, G. Desprez, C. Di Cesare, M. J. Hayes, I. Jermann, G. Kotiwale, I. Kramarenko, D. Langeroodi, S. Mascia, J. Matthee, J. Melinder, A. Muzzin, B. Navarrete, G. Noirot, G. Östlin, F. Pacucci, G. Rodighiero, M. Sawicki, Y. Sun, Z. Wu, G. Yang
Astrophysics of Galaxies
The chemical DNA of the Magellanic Clouds VI. Origin and evolution of neutron-capture elements in the SMC
Marco Palla, Alessio Mucciarelli, Donatella Romano et al. (+2 more)
Context. In the context of
galactic archaeology, the study of the Small Magellanic Cloud (SMC) is of crucial importance, as it represents a unique opportunity to study a nearby massive
dwarf system. However, theoretical studies of the chemical
evolution of this
galaxy are strikingly lacking. Aims. In this study, we investigate the chemical enrichment of the SMC
galaxy. Besides alpha and Fe-peak elements, we devote particular
attention to the
evolution of
neutron-capture elements with different origin, namely r-process (Eu), weak s-process (Zr) and main s-process (Ba, La). Methods. We develop chemical
evolution models that use as input the
star formation histories obtained from colour-magnitude diagram fitting. We follow in detail the chemical feedback provided by a large variety of nucleosynthetic sources. Model predictions are compared with recent abundance measurements for the SMC. Results. The developed framework reproduces well all the observables for elements up to the Fe-peak. The abundance patterns of n-capture elements are simultaneously reproduced only by assuming an enhanced contribution from the delayed r-process at low
metallicity and a top-lighter IMF relative to the reference IMF by Kroupa (2001). In this way, both the observed very high plateau in [Eu/Fe] and the rising trends in [s-process/Fe] ratios can be reproduced by the models. Conclusions. This study provides for the first time information on the
evolution of several n-capture elements in a massive
dwarf irregular
galaxy, also providing insight on several ingredients driving
galactic evolution. Moreover, this work provides a test-bed for further modelling of the SMC in the context of the numerous surveys that will target the Magellanic Clouds in the next years.
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All authors Marco Palla, Alessio Mucciarelli, Donatella Romano, Samuele Anoardo, Francesca Matteucci
Earth and Planetary Astrophysics
The efficient delivery of highly-siderophile elements to the core creates a mass accretion catastrophe for the Earth
Richard J. Anslow, Maylis Landeau, Amy Bonsor et al. (+2 more)
The excess abundance of highly siderophile elements (HSEs), as inferred for the terrestrial
planets and the Moon, is thought to record a `late veneer' of impacts after the
giant impact phase of
planet formation. Estimates for total mass
accretion during this period typically assume all HSEs delivered remain entrained in the mantle. Here, we present an analytical discussion of the fate of
liquid metal diapirs in both a magma pond and a solid mantle, and show that metals from impactors larger than approximately 1 km will sink to Earth's core, leaving no HSE signature in the mantle. However, by considering a collisional size distribution, we show that to deliver sufficient mass in small impactors to account for Earth's HSEs, there will be an implausibly large mass delivered by larger bodies, the metallic fraction of which lost to Earth's core. There is therefore a contradiction between observed concentrations of HSEs, the geodynamics of metal entrainment, and estimates of total mass
accretion during the late veneer. To resolve this paradox, and avoid such a mass
accretion catastrophe, our results suggest that large impactors must contribute to observed HSE signatures. For these HSEs to be entrained in the mantle, either some mechanism(s) must efficiently disrupt impactor core material into $\leq0.01$ mm fragments, or alternatively Earth accreted a significant mass fraction of oxidised (carbonaceous chondrite-like) material during the late veneer. Estimates of total mass
accretion accordingly remain unconstrained, given uncertainty in both the efficiency of impactor core fragmentation, and the chemical composition of the late veneer.
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All authors Richard J. Anslow, Maylis Landeau, Amy Bonsor, Jonathan Itcovitz, Oliver Shorttle
Instrumentation and Methods for Astrophysics
Simulations of a 2 x 1.5D coded aperture camera for X-ray astronomy
J.J.M. in 't Zand, L. Kuiper, F. Ceraudo et al. (+3 more)
The concept of two perpendicular one-dimensional coded aperture cameras, necessitated by the imaging capability of the detector, finds its application in the design of the Wide Field Monitor (WFM). This instrument has the future goal to monitor the variable X-ray sky for transient activity. Characteristic of each camera is a fine angular resolution in one direction (typically 5 arcmin) and a coarse one in the other (5 degrees). The coarse perpendicular resolution makes the camera so-called '1.5D'. The WFM has been studied for a number of space-borne X-ray observatory concepts: LOFT, eXTP, Strobe-X, ARCO and now LEM-X. We here report on a study of two decoding
algorithms for this instrument and its imaging performance. Detector responses to the X-ray sky are simulated, including the signal processing by the front-end and back-end electronics. The decoding
algorithms are the iterative removal of sources (IROS), in combination with cross correlation, and the maximum likelihood method (MLM). IROS is most suited for the determination of the point source configuration of the observed sky and MLM for the optimum determination of the source fluxes. (..) the WFM is a high performance monitoring instrument with straightforward and proven technology that enables the identification of new
cosmic X-ray sources, for instance X-ray novae, gamma-ray bursts and electromagnetic counterparts to gravitational wave events from merging compact objects, and the detection of unusual and interesting behavior of persistent
cosmic X-ray sources, such as
accretion disk state changes.
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All authors J.J.M. in 't Zand, L. Kuiper, F. Ceraudo, Y. Evangelista, M. Hernanz, A. Patruno
Solar and Stellar Astrophysics
The Sunrise Chromospheric Infrared Spectro-Polarimeter SCIP: an instrument for SUNRISE III
Y. Katsukawa, J. C. del Toro Iniesta, S. K. Solanki et al. (+54 more)
The Sunrise balloon-borne
solar observatory is equipped with a one-meter aperture optical
telescope, offering a unique platform for uninterrupted seeing-free observations across ultraviolet, visible, and infrared wavelengths from altitudes higher than 33 km. For the third flight of the upgraded Sunrise observatory conducted in 2024, now called Sunrise III, a new spectro-polarimeter called the Sunrise Chromospheric Infrared spectroPolarimeter (SCIP) was developed for observing near-infrared wavelength ranges around 770 nm and 850 nm. These wavelength ranges contain many spectral lines, including two of the Ca II infrared triplet, K I D1 and D2 lines, and multiple Fe I lines, that are sensitive to
solar magnetic fields and velocities in the photosphere and chromosphere. SCIP consists of a grating spectrograph in which polarimetric measurements are conducted using a rotating waveplate as a modulator and polarizing beam splitters placed in front of the cameras. The spatial and spectral resolutions are 0.21" and 1x10^5, respectively, and a polarimetric sensitivity of 0.03% (1sigma) of the continuum intensity is achieved with a 10 s integration time per a resolution element. To achieve high-precision detection of small polarization signals, we carefully designed the optical and mechanical systems, polarization components, control electronics, and onboard data processing. Together with the other post-focus instrumentation developed for Sunrise III, the Sunrise Ultraviolet Spectropolarimeter and Imager (SUSI) and the visible imaging spectro-polarimeter Tunable Magnetograph (TuMag), SCIP provides novel observations that help elucidate energy transfer and time-dependent phenomena across the
solar photosphere and chromosphere.
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All authors Y. Katsukawa, J. C. del Toro Iniesta, S. K. Solanki, M. Kubo, H. Hara, T. Shimizu, T. Oba, Y. Kawabata, T. Tsuzuki, F. Uraguchi, K. Shinoda, T. Tamura, Y. Suematsu, T. Matsumoto, R.T. Ishikawa, Y. Naito, K. Ichimoto, S. Nagata, T. Anan, D. Orozco Suárez, E. Sanchis Kilders, M. Balaguer Jiménez, A. C. López Jiménez, C. Quintero Noda, D. Álvarez García, J. L. Ramos Mas, J. P. Cobos Carrascosa, P. Labrousse, B. Aparicio del Moral, A. Sánchez Gómez, D. Hernández Expósito, E. Bailón Martínez, J. M. Morales Fernández, A. J. Moreno Mantas, A. Tobaruela, I. Bustamante, F. J. Bailén, J. Blanco Rodríguez, J. L. Gasent Blesa, P. Rodríguez Martínez, A. Ferreres, D. Gilabert Palmer, J. Piqueras Carreño, I. Pérez Grande, I. Torralbo, A. Álvarez Herrero, A. Korpi-Lagg, A. Gandorfer, T. Berkefeld, P Bernasconi, A. Feller, T. L. Riethmüller, H. N. Smitha, V. Martínez Pillet, B. Grauf, A. Bell, M. Carpenter
High Energy Astrophysical Phenomena
Radiative GRMHD simulations of puffy accretion discs: Numerical versus analytical models of sub-Eddington accretion
Debora Lančová, Maciek Wielgus, Marek Abramowicz et al. (+6 more)
A widely accepted picture of an
accretion flow in the luminous soft spectral state of X-ray binary systems is a geometrically thin disc structure much like the classic analytic solution of Shakura& Sunyaev. Although the analytic models are troubled by instabilities and miss important aspects of physics, such as
magnetic fields, they are successfully used as a framework for interpreting observational data. Here, we compare the results of general relativistic radiative magnetohydrodynamic (GRRMHD) simulations of optically thick, mildly sub-Eddington
accretion on a
stellar-mass black hole (the puffy disc) with established analytic and semi-analytic
accretion models in the same regime. From the simulations, we find that the
accretion flow is stabilised by the
magnetic field, with a puffed-up, optically thick region resembling a warm corona surrounding a denser and cooler disc core. However, the stratified vertical structure of the disc significantly influences the observational picture of such a system. We analyse the inner disc structure, flow properties, effective viscosity, and inner edge position, and compare them to the predictions of standard models. We find that the simulated discs share some similarities with the models; however, they differ in several important aspects, most notably: the photosphere is geometrically thick, the inner edge is located closer to the central black hole than the analytic models assume, the surface density is significantly lower than analytically predicted, and the effective viscosity parameter is not constant but rises steeply in the innermost region.
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All authors Debora Lančová, Maciek Wielgus, Marek Abramowicz, Agata Różańska, Włodek Kluźniak, Jiří Horák, David Abarca, Aleksander Sądowski, Gabriel Török
Solar and Stellar Astrophysics
PRODIGE – envelope to disk with NOEMA VIII. Sulfur oxides trace a shock caused by a streamer in the inner envelope of a protostar
María Teresa Valdivia-Mena, Jaime E. Pineda, Caroline Gieser et al. (+24 more)
(Abridged) Recently, streamers have been observed causing shocks at the outer edge of protoplanetary disks. The study of sulfur-bearing species can help us to understand the physical and chemical changes caused by infalling streamers toward their landing positions. We study the physical properties traced by SO$_2$ and SO toward the Class I protostar Per-emb 50, which is possibly related to the streamer infalling toward its disk. We present new NOEMA A-array observations as part of the large program "Protostars and Disks: Global
Evolution" (PRODIGE). We analyzed the morphology of SO$_2$ and SO, and complement our interpretations with additional H_$2$CO and CO data from the same program. We compared the SO$_2$ and SO morphology with an infalling-rotating model. We applied
Bayesian model selection to the brightest SO$_2$ line to disentangle the different kinematic components traced by this molecule. We used Local Thermodynamic
Equilibrium (LTE) and non-LTE analyses to determine the temperature and density of the SO$_2$ emission. There are two separate peaks of SO$_2$ emission offset toward the southwest of Per-emb 50, one brighter (peak 1) at about 180 au from the protostar, and a weaker one (peak 2) at about 400 au. Peak 2 is blueshifted with respect to an infalling-rotating envelope. We propose that this peak is caused by the shock between the inner envelope and the streamer. Peak 1 is consistent with the expected envelope motion, and could thus be caused by shocks at the disk-envelope interface, but potential streamer influence cannot be neglected. Both peaks show abundance ratios consistent with a low velocity shock ($\sim 3-4$ \kms) when compared with shock models. Streamers can affect the physical and chemical structure of both disks and envelopes, suggesting that streamers can play an important role in shaping both structures in the embedded stages of
star formation.
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All authors María Teresa Valdivia-Mena, Jaime E. Pineda, Caroline Gieser, Paola Caselli, Dominique M. Segura-Cox, Yuxin Lin, María José Maureira, Tien-Hao Hsieh, Laura A. Busch, Ana Lopez-Sepulcre, Laure Bouscasse, Dmitry Semenov, Asunción Fuente, Nichol Cunningham, Thomas Henning, Julián J. Miranzo-Pastor, Yu-Ru Chou, Roberto Neri, Izaskun Jimenez-Serra, Edwige Chapillon, Stephane Guilloteau, Felipe Alves, Mario Tafalla, Anne Dutrey, Riccardo Franceschi, Sierk van Terwisga, Kamber Schwarz
Instrumentation and Methods for Astrophysics
Test of a 34 GHz EOM laser frequency comb at ESPRESSO
Tobias M. Schmidt, Ewelina Obrzud, François Bouchy et al. (+18 more)
Laser frequency combs (LFCs) are a promising technology for wavelength calibration of astronomical high-resolution spectrographs requiring utmost accuracy and stability, since they directly translate the fundamental SI time standard from the
radio frequency regime to optical frequencies. However, they have so far seen limited use in practice, due to their complexity, incomplete wavelength coverage, but also the challenges in the data analysis they imply. Here, we present a detailed test of a 34 GHz electro-optic modulation comb with the ESPRESSO spectrograph. Using thin-film lithum-niobate waveguides for broadening and harmonic generation, the setup provides partial coverage of the IR, visible, and near-UV spectral ranges. We focus on assessing the quality of the delivered spectra and their capability to facilitate accurate and stable wavelength calibration. We present a detailed analysis of the spectrally-diffuse background, the line width, and characterize the line-spread function over a broader width than possible with the ESPRESSO facility LFC. Comparing both combs, we find strong local discrepancies in the wavelength calibration accuracy up to 15m/s , which correlate with the echellogram structure. These do not originate from the
lasers, but from misalignments in the ESPRESSO calibration unit, highlighting the strong need to make instrument fiber feeds more robust to light-injection effects. Nevertheless, we demonstrate excellent stability of the wavelength calibration, with a scatter of only 17cm/s . This, however, can only be achieved when accurately modeling the non-Gaussian line-spread function, showcasing the need for advanced data analysis techniques when dealing with LFC spectra.
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All authors Tobias M. Schmidt, Ewelina Obrzud, François Bouchy, Gaspare Lo Curto, Victor Brasch, Tobias Herr, Furkan Ayhan, Severine Denis, Davide Grassani, Jean Berney, Bruno Chazelas, Weichen Fan, Jannis Holzer, Ian Hughes, Markus Ludwig, Antonio Manescau, Luca Pasquini, Francesco Pepe, Luis Guillermo Villanueva, François Wildi, Thibault Wildi
Solar and Stellar Astrophysics · Cross-listed from physics.space-ph
Compressive Structures in the Foreshock of Collisionless Shocks
Savvas Raptis, Domenico Trotta, Drew L. Turner et al. (+11 more)
Collisionless shocks are fundamental accelerators of energetic particles; yet, the observations of nonlinear foreshock structures, which are essential in acceleration processes, differ significantly between Interplanetary (IP) shocks and planetary bow shocks. We present a direct comparison of two high-Mach-number, quasi-parallel shocks: an IP shock observed by
Solar Orbiter and the Earth's bow shock measured by the Magnetospheric Multiscale (MMS) mission during the 2024-2025 “string-of-pearls” campaign. We show that Foreshock Compressive Structures (FCSs) initiate upstream of both shocks at similar normalized distances ($\lesssim$50 ion inertial lengths, $d_i$) when the suprathermal ($>10$ keV) ion density exceeds $\sim$1% of the background. However, the IP shock lacks the fully evolved, high-amplitude Short Large Amplitude
Magnetic Structures (SLAMS) characteristic of the terrestrial foreshock. We demonstrate that the “growth zone” capable of sustaining these structures is spatially limited ($\sim$135 $d_i$), which, due to the high speed of the propagating IP shock, corresponds to a brief observational window of $<10$ s. Beyond this observational constraint, we suggest an additional physical mechanism that can inhibit foreshock maturity at IP shocks. The lack of global
curvature prevents the lateral supply (“cross-talk”) of energetic ions from different shock regions. These findings suggest that while the fundamental physics of FCS initiation is unified across collisionless shocks, the achievement of full nonlinearity can be regulated by the unique shock geometry and upstream properties, while ultimately remaining observationally challenging to identify.
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All authors Savvas Raptis, Domenico Trotta, Drew L. Turner, Xóchitl Blanco-Cano, Heli Hietala, Tomas Karlsson, Immanuel Christopher Jebaraj, Ivan Y. Vasko, Adnane Osmane, Kazue Takahashi, David Lario, Lynn B. Wilson III, Gregory G. Howes, Robert F. Wimmer-Schweingruber
Solar and Stellar Astrophysics
Kinetic-based macro-modeling of the solar wind at large heliocentric distances: Kappa electrons at the exobase
Alexander Vinogradov, Marian Lazar, Ioannis Zouganelis et al. (+2 more)
Recent evidence from Parker
Solar Probe on the suprathermal electrons with Kappa-type velocity distributions in the outer corona has revived interest in the kinetic-based macro-modelling of the
solar (SW), aiming to explain its properties. Invoked in kinetic modelling of nonequilibrium
plasmas, standard Kappa distributions (SKDs) have been adjusted to the regularized Kappa distributions (RKDs) to fix the inconsistencies of SKD and develop consistent fluid modelling of space
plasmas. We propose a new analysis of these properties at large heliocentric distances based on the existence of RKD electrons at the exobase. This new semi-analytic formalism is inspired by the methodology proposed initially by Meyer-Vernet and Issautier (1998), https://doi.org/10.1029/98ja02853. Compared to SKDs, the results for RKDs have extended applicability, since all moments can be defined and calculated consistently for all values of the $\kappa$ parameter, even lower than the critical ones (e.g., $\kappa_c=3/2$ imposed to the second-order moment) of SKDs. However, the excess energy of the more energetic suprathermal electrons associated with low values of $\kappa \lesssim 3/2$, is regulated by the RKD-specific cutoff parameter $\alpha < 1$. The estimates for, e.g., the temperature and bulk velocity of the SW, remain at realistic values even for small $3/2 < \kappa \lesssim 2$, which would otherwise exceed specific observations. One can thus model a higher abundance of suprathermal electrons at the exobase (e.g., $\kappa \leqslant 3/2$), which is plausible for the sources of energetic events (
flares and coronal mass ejections), and also in the astrospheres of
stars with coronas hotter than the Sun's.
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All authors Alexander Vinogradov, Marian Lazar, Ioannis Zouganelis, Viviane Pierrard, Stefaan Poedts
Cosmology and Nongalactic Astrophysics
The Revised Evolutionary Volume Tolman Test: Cosmological Constraints from Galaxy Evolution
Christopher J. Conselice, Edmund J. Copeland and Sergio Sevillano Muñoz
In this study we adapt a classical cosmology measurement, the volume or number density test, to a modern synthesis of observed
galaxy evolution. We do this by using measured
galaxy mass functions and the history of
galaxy evolution through
star formation and
galaxy mergers, inspired by the latest results from deep extragalactic surveys. We develop a new framework using measured
galaxy volume number densities as a function of
redshift and volume to determine cosmological parameters, especially those which alter the volume of the Universe at a given
redshift. Whilst this is a classic cosmology test proposed since at least the 1930s, it has largely been abandoned for decades due to uncertainties in
galaxy evolution which make it difficult to trace
galaxy populations through time. However, recent advances in our understanding of
star formation and the merging history of
galaxies allow us to revise this method to uncover and measure cosmological parameters, especially those which involve the nature of dark energy. We present a modified version of the volume test, called the revised evolutionary volume Tolman test, using properties of known
galaxy evolution as part of the cosmological calculation. We show how this method can successfully be applied and is competitive with other major cosmological measurement methods, including those using
supernova and the CMB, when the merger and
star formation histories can be measured accurately to between 1 to 10 percent. This accuracy is not yet achievable, but we discuss how future missions will allow these astrophysical quantities to be known at this level. Within this measurement accuracy we can measure the dynamical properties of dark energy, including its
evolution through its equation of state. We also give a fuller accounting of the future use of this new method with upcoming
galaxy surveys such as Euclid and LSST/Rubin.
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Cosmology and Nongalactic Astrophysics
Enhanced foreground mitigation in thermal SZ Compton-$y$ maps via polarization and deprojection
Jyothis Chandran, Mathieu Remazeilles and R. B. Barreiro
Residual foreground contamination in thermal Sunyaev-Zeldovich (SZ) Compton-$y$ parameter maps ($y$-maps) arises mainly from
Galactic emissions – thermal
dust and synchrotron radiation – on large angular scales, and from
cosmic infrared background (CIB) anisotropies on small scales. Unlike the thermal SZ effect,
Galactic foregrounds are strongly polarized. Exploiting this distinction, we introduce a hybrid Needlet Internal Linear Combination (Hybrid NILC) method that combines Planck total-intensity and polarization frequency maps in the component-separation pipeline, thereby improving the suppression of residual
Galactic emission while preserving the unpolarized SZ signal by leveraging the intrinsic $TE$ and $TB$ correlations of thermal
dust and synchrotron. Using Planck PR4 data, we find that the Hybrid NILC $y$-map exhibits about $40\,\%$ lower cross-correlation with the IRAS
dust tracer than the standard temperature-only Planck $y$-map, indicating reduced residual
Galactic contamination. Simulations further indicate that, for future high-sensitivity surveys such as LiteBIRD, the Hybrid NILC will become increasingly effective at suppressing
Galactic residuals. We further address small-scale extragalactic contamination by selectively deprojecting specific moments of the CIB using a Constrained Hybrid NILC variant, achieving an improved balance between CIB suppression and noise penalty compared to previous implementations in the literature. These novel approaches – particularly the joint use of temperature and polarization in component separation – offer a powerful framework for disentangling polarized and unpolarized signals.
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Astrophysics of Galaxies
The effects of bar strength and kinematics on galaxy evolution II: The global and local impacts of slow-strong bars
Petra Mengistu, Karen L. Masters, Tobias Geron et al. (+3 more)
There is now clear evidence, from a variety of studies, that
galactic bars contribute to and/or accelerate processes which quench
galaxies. However, bars have a variety of strengths and pattern speeds, and previous work has suggested that slow and strong bars impact their hosts the most. In this paper, we continue to investigate the impact of bar strength and bar speed on host
galaxy evolution in a sample of barred
galaxies identified via classifications from
Galaxy Zoo. We perform a comprehensive assessment of
star-formation tracers spanning a variety of timescales, based on spatially resolved spectroscopic information from the Mapping Nearby
Galaxies at Apache Point Observatory (MaNGA) survey. Specifically, we examine the radial distributions of EW[Halpha], HdeltaA, Hbeta, and Dn4000; spectral data that trace
star-formation on current, intermediate, and much longer timescales. We investigate how these
star-formation tracers vary with respect to each other in diagnostic evolutionary planes for eight categories of barred
galaxies (combinations of
star forming or quenching; strong and weak; fast and slow). We continue to find that slow-strong bars drive the quenching of their hosts the most by triggering active
star-formation throughout the barred region; however, we note some additional complexity: we observe that stronger bars boost
star-formation at the bar centre while slower bars have increased
star-formation along the bar. This work adds to the growing evidence that
galactic bars have both global and local impacts on their host
galaxies.
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All authors Petra Mengistu, Karen L. Masters, Tobias Geron, R.J. Smethurst, Chris Lintott, B.D. Simmons
Astrophysics of Galaxies
Gravity anomaly from laboratory experiments to astrophysics
Riccardo Scarpa, Renato Falomo and Aldo Treves
Modifications to Newtonian dynamics at low accelerations have long been proposed as an alternative to dark matter to explain
galaxy rotation curves. More recently, similar corrections have been invoked to interpret anomalies in Cavendish-type laboratory experiments and in the dynamics of wide binary
stars, although the latter remain affected by ongoing observational debate. We show that, if deviations from Newtonian
gravity occur in the low-acceleration regime, the available data are broadly consistent with a MOND-like interpretation. In this framework, wide binary systems appear to extend the Tully-Fisher relation, well established for
galaxies, to much smaller mass scales. Taken together, departures from Newtonian predictions at low accelerations in
galaxies, wide binaries, and laboratory experiments may point to a common physical scenario.
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Cosmology and Nongalactic Astrophysics
Inflation with the Gauss-Bonnet term in the Palatini formulation
Ali Hassan and Syksy Rasanen
We consider the Gauss-Bonnet term coupled to the inflaton in the Palatini formulation of
gravity. Unlike in the metric formulation, the Gauss-Bonnet term is not always a total derivative. We solve for the connection and insert it into the action, exactly for the spatially flat FLRW spacetime, and using the gradient approximation and order reduction for a general spacetime. We consider three cases: when the connection is unconstrained, and when non-metricity or torsion is put to zero. In all cases, the leading order change to the inflaton kinetic has the same form as that generated by the Chern-Simons term, but a negative sign. The modification of the gravitational wave sector also has the same form as in the Chern-Simons case but with a negative sign, except possibly for zero torsion, depending on the coupling and the potential. Within the range of validity of our approximations, differences from the metric formulation are small unless the kinetic term flips sign or is close to doing so.
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Astrophysics of Galaxies
Interstellar Dust Transport Through the Heliosphere Including the Sector Region
Jonathan D. Slavin, Marc Kornbleuth, Merav Opher et al. (+1 more)
Interstellar
dust has been detected in situ flowing through the heliosphere. However, our ability to derive the density and size distribution of the interstellar
dust in the local interstellar medium from this directly detected
dust requires modeling the transport of the grains as they interact with the
solar wind
magnetic field. The
magnetic field in the sector region that contains the heliospheric current sheet has rapid polarity flips which can present an effectively very low averaged field strength to
dust grains that have gyroradii tens of au in size. We present new calculations of
dust transport through the heliosphere using models that include the sector region to assess the effects on
dust transport. We show that the sector region can act as a window allowing even relatively small grains to penetrate deep into the heliosphere. We find the sector region reduces the variation in
dust density with the
solar cycle (as compared to models without the sector region), with very little concentration or dilution of the
dust for grains larger than \sim 0.1$ $\mu$m for most of the
solar cycle. We still find a substantial concentration of the
dust in the ecliptic plane for a focusing overall polarity of the field at
solar minimum. These models do not include the time dependence of the
magnetic field during transport of grains through the heliosphere. Nevertheless, our results imply that observations of interstellar
dust grains, even near Earth, could be fairly accurate in determining their size distribution in the surrounding interstellar medium.
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All authors Jonathan D. Slavin, Marc Kornbleuth, Merav Opher, Gabor Toth
Instrumentation and Methods for Astrophysics
Long-algorithm based quantum search for gravitational wave
Fangzhou Guo and Jibo He
Gravitational wave astronomy is rapidly advancing with the development of new observatories, leading to an increasing volume and complexity of data. This trend places growing pressure on classical data analysis methods and motivates the exploration of
quantum approaches. In this work, we introduce a
quantum matched filtering framework for gravitational-wave detection based on the Long
algorithm, marking its first application to the gravitational-wave data analysis. Numerical simulations show that the proposed approach preserves the quadratic speedup of
quantum search while exhibiting significantly improved robustness, thereby overcoming key limitations of the Grover-
algorithm based methods.
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Solar and Stellar Astrophysics
A 3D physico-chemical model of a pre-stellar core. II. Dynamic chemical evolution in a pre-stellar core model using tracer particles
S. S. Jensen, S. Spezzano, P. Caselli et al. (+3 more)
This work explores the differences between static and dynamically evolving physico-chemical models of pre-
stellar cores. A 3D MHD model of a pre-
stellar core embedded in a dynamic
star-forming cloud is post-processed using sequentially
dust radiative transfer, a gas-grain chemical model, and a non-LTE line-radiative transfer model. The chemical
evolution is modeled along $\sim$20,000 tracer particle trajectories to capture the impact of a realistic dynamical
evolution as the core is formed. The emission morphology of CH$_3$OH and $c$-C$_3$H$_2$ and the intensities of CH$_3$OH, $c$-C$_3$H$_2$, CS, SO, HCN, HCO$^+$ and N$_2$H$^+$ are compared with observations of L1544. Our results show a distinct difference in chemical morphology between the dynamical and static models. The dynamical model reproduces the observed spatial distribution of CH$_3$OH and $c$-C$_3$H$_2$ toward L1544, whereas the static model fails to reproduce this morphology. In contrast, when comparing modeled and observed intensities across a broad range of molecules, the static model shows good agreement with observations for L1544. The dynamical model systematically predicts lower abundances and modeled intensities for six of the seven species presented here. For sulphur-bearing species, the intensities are in better agreement with observations when the initial abundances are undepleted in heavier elements. This study reveals distinct differences between dynamical and static physico-chemical models. The static model predicts higher abundances and intensities for the majority of the molecules studied here, compared with the dynamical model. This discrepancy may stem from the specific choices of initial conditions, which could limit the dynamical models ability to fully capture the physical and chemical history. The intensities predicted by the static model are comparable to those observed toward L1544.
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All authors S. S. Jensen, S. Spezzano, P. Caselli, T. Grassi, O. Sipilä, T. Haugbølle
Astrophysics of Galaxies
The Engine and its Flows: Little Red Dot spectra are shaped by the column densities of their gas envelopes
Jorryt Matthee, Alberto Torralba, Gabriele Pezzulli et al. (+23 more)
JWST data have enabled the abundant identification of compact broad Balmer line sources nicknamed the Little Red Dots. While they share broad lines with active
galactic nuclei, they are unusually X-ray and infrared weak. We investigate the origin of the Balmer line profiles based on an empirical analysis of 18 broad H$\alpha$-selected sources with high quality spectra at $z\approx3-7$. The H$\alpha$ line profiles vary systematically with Balmer break strength: sources with blue UV to optical colors show a narrow core profile, redder sources with Balmer breaks a blue shifted absorption (P Cygni shape), and the reddest sources display absorption-dominated cores. All H$\alpha$ lines have symmetric exponential wings, which are more dominant and slightly broader in red sources. Balmer absorption is present in $\sim60$ % of the sample, with H$\beta$ showing relatively stronger absorption. Drawing upon empirical analogies with
stellar phenomena, we interpret these trends as being due to radiative processes that depend on variations in the optical depth, ionisation state and column density of a clumpy, partially ionised envelope. We unveil a correlation between the absorber velocity and Balmer break strength, with the densest absorbers inflowing and bluer sources having faster
outflows. This indicates viewing angle or evolutionary effects where optically thick gas is inflowing, as suggested in models of super-Eddington
accretion, and the engine can more easily drive
outflows in directions with lower column densities. This new understanding of Balmer line profiles as tracing gas properties rather than dynamical broadening helps resolve tensions associated with high inferred black hole masses from standard virial calibrations, and reveals the complex gas environment around the hot central engine.
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All authors Jorryt Matthee, Alberto Torralba, Gabriele Pezzulli, Rohan P. Naidu, John Chisholm, Sara Mascia, Jenny E. Greene, Yuzo Ishikawa, Max Gronke, Stijn Wuyts, Rongmon Bordoloi, Gabriel Brammer, Seok-Jun Chang, Anna-Christina Eilers, Anna de Graaff, Raphael E. Hviding, Edoardo Iani, Garth Illingworth, Daichi Kashino, Ivo Labbe, Yilun Ma, Michael V. Maseda, Romain Meyer, Erica Nelson, Pascal Oesch, Mengyuan Xiao
Cosmology and Nongalactic Astrophysics · Cross-listed from gr-qc
Modified Friedmann equations and non-singular cosmologies in $d=4$ non-polynomial quasi-topological gravities
Johanna Borissova and João Magueijo
Quasi-topological theories of
gravity are known to resolve black-hole singularities. We investigate whether the same mechanism can remove cosmological singularities. Focusing on non-
polynomial curvature quasi-topological gravities in $d=4$ dimensions, we find three generic scenarios with the correct infrared limit but without a Big-Bang singularity, for universes filled with pure radiation or other standard matter. The first scenario yields a universe emerging from a de Sitter phase, a case for which the
curvature invariants remain finite but the matter density diverges, albeit only at infinite affine distance. The second one corresponds to a bouncing universe, which requires a multi-valued Lagrangian. The third possibility is an asymptotically Minkowski origin, reminiscent of an eternally loitering universe. The matter energy density for this solution is non-singular even at infinite affine distance and does not enter a super-Planckian regime, but is instead approximately constant for the past eternity.
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High Energy Astrophysical Phenomena
Scatter in the Relation between Persistent Radio Source Luminosity and Fast Radio Burst Rotation Measure: A Window into Circum-burst Environments
Yuan-Pei Yang
The association of persistent
radio sources (PRSs) with repeating fast
radio bursts (FRBs) offers unique insights into their circum-burst environments. Building upon the physical link between PRS luminosity ($L_\nu$) and FRB rotation measure (RM), we introduce a novel diagnostic framework utilizing the intrinsic scatter of the $L_\nu - |{\rm RM}|$ relation as a physical probe of nebula dynamics. We show that this scatter encodes critical information regarding the temporal
evolution of the nebula radius ($R \propto t^\alpha$). By deriving a generic scaling $L_\nu \propto R^\epsilon |{\rm RM}|$, we apply this framework to the current sample of five confirmed FRB-PRS systems as a proof-of-concept. Our preliminary analysis yields a combined evolutionary index of $\alpha|\epsilon| = 1.5 \pm 0.8$. This measurement illustrates the potential of our methodology to distinguish among diverse astrophysical scenarios, such as
supernova remnants (SNRs) in different evolutionary stages,
pulsar wind nebulae (PWNe) driven by constant wind or varying winds, and binary bow-shock systems. While the current conclusions are limited by the small sample size, this work establishes a robust statistical methodology for future population studies. As next-generation
radio surveys localize a larger population of active repeaters, this framework will serve as a powerful tool to statistically constrain the physical origin and dynamical life cycle of FRB circum-burst environments.
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High Energy Astrophysical Phenomena
A high-resolution X-ray view of the ultra-fast outflow in MAXI J1810-222
C. Pinto, M. Del Santo, A. D'Aì et al. (+10 more)
In previous work, it was reported that the
Galactic black hole candidate MAXI J1810-222 exhibited a notable absorption spectral feature at around 1 keV in low-resolution X-ray spectra of CCD-like detectors. The feature was correlated with the spectral state of the source, being stronger in the soft states, as it occurs in the typical Fe K winds of X-ray binaries (XRBs). However, the results hinted towards rather extreme wind velocities of up to ~0.1 c. We therefore requested and obtained an observation with XMM-Newton to take advantage of the 10-fold higher spectral resolution (R ~200-400) provided by the RGS detector in order to resolve the lines and break the degeneracy between different models and interpretations. We applied state-of-the-art models of
plasma in photoionisation
equilibrium and multiphase interstellar medium. Further comparisons are performed with a re-analysis of NICER and NuSTAR data. The XMM-Newton/RGS spectrum is consistent with the presence of a mildly relativistic wind, confirming the earlier indications obtained with NICER, but places tighter constraints on the
outflow properties, with the lines being intrinsically broad. The data would then favour magnetically driven winds, although thermal effects may still contribute to mass loading. NuSTAR and XMM-Newton (EPIC) show a further hotter component indicating a stratified or multiphase
outflow. Fe K spectra taken with calorimetric detectors (e.g., Resolve on XRISM) will enable a high-resolution view of the complex extreme
outflow in this source and shed new light on
outflow processes in XRBs.
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All authors C. Pinto, M. Del Santo, A. D'Aì, F. Pintore, T. D. Russell, M. Parra, J. Ferreira, P.-O. Petrucci, K. Fukumura, A. Marino, T. Muñoz-Darias, G. A. Rodríguez Castillo, A. Segreto
Astrophysics of Galaxies
RABBITS - III. Modelling relativistic accretion discs around spinning black holes in galaxy formation simulations
Dimitrios Irodotou, Shihong Liao, Theodoros Nakas et al. (+6 more)
In this third study of the 'Resolving supermAssive Black hole Binaries In
galacTic hydrodynamical Simulations' (RABBITS) series we develop and implement a geometrically thin relativistic
accretion disc model, which self-consistently evolves the mass and
spin vector of black holes via analytically modelling the structure of steady-state
accretion discs. The model employs a suite of relativistic, local solutions where pressure is dominated by either gas or radiation, while opacity is primarily governed by either electron scattering or free-free absorption. These local solutions are piece-wisely combined to form the global structure of the
accretion disc based on each solution's range of validity. By explicitly modelling the structure of
accretion discs, the model mitigates the stochasticity inherent in Bondi-type prescriptions, resulting in an approach where every episode of black hole mass
accretion is derived from first principles. For the first time, our model enables
galaxy formation simulations to place constraints on
accretion disc sizes and structures. In addition, flux and temperature radial profiles can be directly extracted from the simulation, enabling the generation of spectral energy distributions. Consequently, by incorporating the thermal structure and spacetime geometry around spinning black holes, our model more accurately captures the energetic output of
quasars, overcoming critical limitations of classical approaches. Along with this manuscript, we make public a C version of the model appropriate to be used as a module in simulations, a Python version of the model that can be used independently to post-process any simulation and build mock
accretion discs, and an updated version of the Relagn model that has the capability of producing SEDs by building an
accretion disc for a given set of parameters and extracting its surface density, temperature, and opacity profiles.
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All authors Dimitrios Irodotou, Shihong Liao, Theodoros Nakas, Geoffrey Compère, Roberto Oliveri, Jessica M. Hislop, Alexander Rawlings, Sonja Soininen, Aswin P. Vijayan
Earth and Planetary Astrophysics
Searching for Molecular Signatures in 14 Transiting Exoplanets with SPIRou
A. Masson, S. Vinatier, B. Bézard et al. (+6 more)
High-resolution spectroscopy provides unique constraints on
exoplanet atmospheric composition and dynamics. The past decade of ground-based campaigns has accumulated extensive public archives, yet many observations remain unanalysed. We present a homogeneous blind-search analysis of 50 SPIRou transits spanning 14
exoplanets, ranging from super-Earths to ultra-hot Jupiters, combining data from large program and public archived observations. Using automated data reduction and atmospheric
retrieval via Nested Sampling validated by Cross Correlation Function analysis, we confirm previous H2O and CO detections in HD 189733 b, WASP-76 b, and WASP-127 b, report tentative H2S detections in HD 189733 b and TOI-1807 b, tentative detection of GJ 3470 b's atmosphere, and provide upper limits for non-detections. This work demonstrates a scalable method for systematic archive analysis, providing a first step toward ground-based support of large space-based atmospheric characterization programs and the study of atmospheric diversity across
exoplanet populations from a statistical perspective.
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All authors A. Masson, S. Vinatier, B. Bézard, F. Debras, A. Carmona, J. Lillo-Box, N. B. Cowan, V. Yariv, R. Allart
Solar and Stellar Astrophysics
Photometric masses for long period CVs: the case study of CSS131106
M. Das, S. P. Littlefair, S. G. Parsons et al. (+15 more)
We present high-speed photometry of the eclipsing cataclysmic variable CSS131106 J052412+004148. We determine the system parameters by modelling the eclipse lightcurve using the photometric eclipse method, in which the mass ratio is determined from the relative timings of the white
dwarf and bright spot eclipses. Despite the blended white
dwarf and bright spot ingress, typical of longer period cataclysmic variables, we perform simulations that show we are able to reliably constrain the component masses. We find a mass ratio of $q = 0.81 \pm 0.06$ and inclination $i = 78.5 \pm 0.7$ degrees. The white
dwarf and donor masses were found to be $M_{w} = 0.72 \pm 0.04 \, M_{\odot}$ and $M_{d} = 0.58 \pm 0.06 \, M_{\odot}$ respectively. The white
dwarf temperature was estimated to be $T_{\rm eff} = 18~500 \pm 2~000$ K, implying a moderate
accretion rate of $\dot{M} = 3 \pm 1 \times 10^{-10} M_{\odot}$ yr$^{-1}$. The donor in CSS131106 J052412+004148 joins two other long-period cataclysmic variables (IP Peg and HS 0220+0031) in being unusually small for its mass, even when compared to detached M-
dwarfs. The donors in all three systems are also unusually cool for their mass. We discuss possible explanations for the small radii and cool temperatures of the donors in these systems, but find no viable explanation for their properties.
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All authors M. Das, S. P. Littlefair, S. G. Parsons, V. S. Dhillon, M. J. Dyer, A. J. Brown, J. A. Garbutt, M. J. Green, D. Jarvis, M. R. Kennedy, P. Kerry, E. Pike, D. I. Sahman, Amalie Yates, J. McCormac, N. Castro Segura, J. Munday, I. Pelisoli
Cosmology and Nongalactic Astrophysics
Forecasting Sensitivity to Modified Dispersion Effects in Pulsar Timing Arrays
Jonathan Grée, Qiuyue Liang and Elisa G. M. Ferreira
The
pulsar timing array systems have reported a detection of a nanohertz-band
stochastic gravitational wave background in our
galaxy. It is of interest to use this observation to probe modified
gravity and to forecast the sensitivity with which certain deviations can be tested in the coming years. In this paper, we focus on the modified dispersion relation of the tensor modes and its effect on the overlap reduction function of the timing residual cross-correlations. We perform a comprehensive forecast of the phase velocity uncertainty, $\sigma_v$, using a Fisher analysis validated by a mock-data study to account for potential non-Gaussian behavior. We also take into account the sample variance effect and provide an observational timeline for future PTA sensitivity: detecting a $10\%$ or $-1\%$ deviation from the speed of light at the $3\sigma$ level requires $\mathcal{O}(30)$ years of observations.
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Earth and Planetary Astrophysics
Mass Inventory of the Solar System Beyond the Sun: A Systematic Compilation with Uncertainty Budget
Mario Menichella
We compile a systematic mass inventory of the
Solar System excluding the Sun, drawing on spacecraft measurements, planetary ephemerides, and population surveys of small-body populations including main-belt asteroids and trans-Neptunian objects. Using a Monte Carlo simulation with 100,000 realisations, and treating poorly constrained components (scattered disc, Oort cloud) as log-normal distributions, we obtain a total non-
solar mass of 462 Earth masses (median), with a 68% credible interval of [451, 515] Earth masses and a 90% credible interval of [449, 642] Earth masses. The
giant planets dominate the mass budget (96.2% of the total). A variance decomposition shows that 98.2% of the total uncertainty is attributable to a single component: the inner Oort cloud (Hills cloud), for which no direct observational constraints exist. The current small-body populations retain only ~0.2% of the
primordial trans-Neptunian disc mass inferred from Nice model simulations, and ~0.04% of the
primordial asteroid belt mass implied by the Grand Tack hypothesis. We identify constraints on the Oort cloud from the Vera C. Rubin Observatory and improved long-period comet surveys as the primary path toward a better-determined total mass budget.
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High Energy Astrophysical Phenomena
The Potential for Hadronic Particle Acceleration in Galactic Pulsar Wind Nebulae
Alison M. W. Mitchell and Samuel T. Spencer
Pulsar wind nebulae (PWNe), formed when the wind originating from a rapidly rotating
neutron star flows out into its surroundings, have now been observed across the electromagnetic spectrum from the
radio to the PeV gamma-ray regime. For most of these sources, leptonic processes, where electrons interacting with background
photon fields produce high-energy
photons through inverse Compton scattering, are believed to be the origin of associated very-high-energy gamma-ray emission. As such, these objects cannot contribute significantly to the
galactic hadronic
cosmic ray flux at ~TeV-PeV energies. However, in a handful of cases, the possibility for an energetically sub-dominant
hadron population being accelerated and producing very to ultra-high energy gamma-rays through pion decay has not yet been comprehensively excluded. Such scenarios have received renewed
attention in the light of recent results from the Large High Altitude Air Shower Observatory (LHAASO). In this review we explore the theoretical background positing hadronic acceleration in
galactic PWNe, considering cases where the
hadrons escape from the
pulsar surface and/or are accelerated in the wind, as well as potential 'shock mixing' scenarios. We also explore current and future possible constraints on a hadronic component to PWNe from observations.
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Astrophysics of Galaxies
Why Are Some Optically Red Spirals NUV-r Blue?
Rui Guo, Cai-Na Hao, Xiaoyang Xia et al. (+2 more)
To understand the complicated formation processes of disk
galaxies, we carry out a comparative study for NUV-r blue and red spiral
galaxies drawn from a parent sample of u-r red spirals with $M_{*} > 10^{10.5} M_{\odot}$ at 0.02 < z < 0.07, based on the optical data from the Sloan Digital Sky Survey (SDSS) and the ultraviolet (UV) data from the
Galaxy Evolution Explorer (GALEX). The analyses of the images and surface brightness profiles in the NUV and optical bands show that the differences between NUV-r blue and red spirals mainly occur in the outer disks (1-3 $R_{\rm e}$), and the contrast in NUV band is much larger than that in the optical bands. Both the positions on the
star formation main sequence diagram and the NUV-r color profiles suggest that NUV-r red spirals have been fully quenched, whereas NUV-r blue spirals host quenched bulges and inner disks, as well as
star-forming outer disks. Particularly, the disk mass-size relations indicate that, at a given disk mass, NUV-r blue spirals possess larger optical disks than NUV-r red spirals, by a factor of $\sim 1.20$. The environments and optical morphologies are consistent with the scenario that NUV-r blue spirals obtained fresh fuel for
star formation either by interacting or merging with gas-rich
galaxies or through accreting surrounding HI gas.
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All authors Rui Guo, Cai-Na Hao, Xiaoyang Xia, Yong Shi, Lan Wang
High Energy Astrophysical Phenomena
VERITAS Observations Contemporaneous with the LHAASO Detection of NGC 4278
The VERITAS Collaboration: A. Archer, P. Bangale, J. T. Bartkoske et al. (+65 more)
Significant gamma-ray emission between 1 TeV and 20 TeV from a point source, 1LHAASO J1219+2915, consistent with the location of the LINER/LLAGN
galaxy NGC 4278 was recently reported by the LHAASO collaboration. These data were later split into active and quasi-quiet states, with most of the LHAASO significance coming from the active state (MJD 59449-59589). Subsequent analysis of
Fermi-LAT and Swift-XRT observations have been used to explore the double-peaked broad-band emission. Models of the spectral energy distribution (SED) are currently unconstrained due to the lack of contemporaneous multi-wavelength data at either peak. Here we report serendipitous observations of NGC 4278 with VERITAS, made possible by the contemporaneous observations of the nearby blazars 1ES 1218+304, 1ES 1215+303, and W Comae, each of which are located within $2^\circ$ of NGC 4278. VERITAS did not detect any gamma-ray emission and a flux upper limit was calculated. The flux upper limits constrain the
photon spectrum of the quasi-quiet period, and together with
Fermi-LAT, indicate a peak in the SED between 100 GeV and 2 TeV. We present an interpretation of the broadband SED that is based on acceleration of
protons in the corona of the AGN, followed by p-$\gamma$ interactions and optically thin $\gamma$-ray emission. Within this framework, the implied
neutrino signal is slightly below the current sensitivity of IceCube.
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All authors The VERITAS Collaboration: A. Archer, P. Bangale, J. T. Bartkoske, W. Benbow, J. H. Buckley, Y. Chen, J. L. Christiansen, A. J. Chromey, A. Duerr, M. Errando, M. Escobar Godoy, S. Feldman, Q. Feng, S. Filbert, L. Fortson, A. Furniss, W. Hanlon, O. Hervet, C. E. Hinrichs, J. Holder, Z. Hughes, T. B. Humensky, M. Iskakova, W. Jin, M. N. Johnson, M. Kertzman, M. Kherlakian, D. Kieda, T. K. Kleiner, N. Korzoun, S. Kumar, S. Kundu, M. J. Lang, M. Lundy, G. Maier, C. McSorley, P. Moriarty, R. Mukherjee, W. Ning, S. O'Brien, M. Ohishi, M. A. Ong, A. Pandey, C. Poggemann, M. Pohl, E. Pueschel, J. Quinn, P. L. Rabinowitz, K. Ragan, P. T. Reynolds, D. Ribeiro, L. Rizk, E. Roache, I. Sadeh, L. Saha, H. Salzmann, M. Santander, G. H. Sembroski, R. Shang, M. Splettstoesser, D. Tak, A. K. Talluri, I. Thoreson, J. V. Tucci, J. Valverde, D. A. Williams, S. L. Wong, T. Yoshikoshi