Earth and Planetary Astrophysics
TOI-333b: A Neptune Desert planet around a F7V star
Douglas R. Alves, James S. Jenkins, José I. Vinés et al. (+29 more)
Observations have shown that
planets similar to Neptune are rarely found orbiting Sun-like
stars with periods up to ~4 days, defining the so-called Neptune desert region. Therefore, the detection of each individual
planet in this region holds a high value, providing detailed insights into how such a population came to form and evolve. Here we report the detection of TOI-333b, a Neptune desert
planet with a mass, radius, and bulk density of 20.1 $\pm$ 2.4 M$_{\oplus}$, 4.26 $\pm$ 0.11 R$_{\oplus}$, and 1.42 $\pm$ 0.21 \gccc, respectively. The
planet orbits a F7V
star every 3.78 d, whose mass, radius and effective temperature are of 1.2 $\pm$ 0.1 \msun, 1.10 $\pm$ 0.03 \rsun, and 6241$^{+73}_{-62}$ K, respectively. TOI-333b is likely younger than 1 Gyr, which is supported by the presence of the doublet Li line around 6707.856 textup{~Å} and its comparison to Li abundances in open clusters with well constrained ages. The
planet is expected to host only 8.5$^{+10.9}_{-8.3}\%$ gas-to-core mass ratio for a H/He envelope. On the other hand, irradiated ocean world models predict 20$^{+11}_{-10}\%$ H$_2$O mass fraction with a core fraction of 35$^{+20}_{-23}\%$. Therefore, we expect that TOI-333b internal composition may be dominated by a pure rocky composition with almost no H/He envelope, or a rocky world with almost equal mass fraction of water. Finally, TOI-333b is more massive and larger than 77$\%$ and 82$\%$ of its Neptune desert counterparts, respectively, while its host ranks among the hottest known for Neptune Desert
planets, making this system a unique laboratory to study the
evolution of such
planets around hot
stars.
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All authors Douglas R. Alves, James S. Jenkins, José I. Vinés, Maximilano Moyano, David R. Anderson, Christian Magliano, Giovanni Covone, Keivan G. Stassun, Abderahmane Soubkiou, Edward Gillen, Matthew P. Battley, Alexander Hughes, David J. Armstrong, Suman Saha, Faith Hawthorn, Peter J. Wheatley, Karen A. Collins, Richard P. Schwarz, Gregor Srdoc, Ioannis Apergis, Tafadzwa Zivave, Monika Lendl, Benjamin M. Tofflemire, John P. Doty, Christina Hedges, Ismael Mireles, Matthew R. Burleigh, Alicia Kendall, George T. Harvey, Michael R. Goad, Sarah L. Casewell, Troy Edkins
Earth and Planetary Astrophysics
The atmospheric composition of TOI-270 d
Savvas Constantinou, Nikku Madhusudhan and Måns Holmberg
The first explorations of temperate sub-Neptune
exoplanets have been the hallmark of early JWST observations. The bulk properties of such
planets are consistent with a range of possible internal structures, which can be distinguished through their interactions with the observable atmospheres. JWST observations of TOI-270 d, a temperate sub-Neptune, have previously led to contrasting conclusions: either a Hycean world, possessing a
liquid water ocean, or a mixed-envelope sub-Neptune, where high temperatures prevent a
liquid ocean and lead to a high mean molecular weight atmosphere. In order to resolve this uncertainty, we present a comprehensive
retrieval analysis of TOI-270 d using recent NIRISS and NIRSpec transit spectroscopy across $\sim$1-5 $\mu$m. We find that prior inferences of a mixed envelope were affected by specific modelling choices leading to a high terminator temperature and high mean-molecular weight in the atmosphere. We confirm an H$_2$-rich atmosphere in TOI-270 d and present revised constraints on the molecular log-mixing ratios and maximal detection significances of CH$_4$ at $-1.86^{+0.30}_{-0.29}$ (6.4 $\sigma$), CO$_2$ at $-1.71^{+0.38}_{-0.66}$ (3.9 $\sigma$), H$_2$O at $-1.88^{+0.78}_{-4.13}$ (2.1 $\sigma$) and CS$_2$ at $-4.74^{+0.65}_{-1.10}$ (2.0 $\sigma$), with a terminator temperature of $323^{+58}_{-52}$ K at 10 mbar. We also find tentative evidence for more complex methyl-bearing species such as C$_2$H$_6$ and/or DMS at a 2.1-2.5 $\sigma$ level. The present constraints are consistent with TOI-270 d being a Hycean or dark Hycean world, with
planet-wide or nightside
liquid water oceans. However, more observations are required to verify the present findings and robustly constrain the atmospheric conditions and internal structure of TOI-270 d.
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Astrophysics of Galaxies
The observed total star formation rate function up to z \sim 6: complementary UV and IR contributions and comparison with state-of-the-art galaxy formation models
A. Traina, C. Gruppioni, I. Delvecchio et al. (+21 more)
We investigate how the obscured IR-derived and the
dust-corrected UV
star formation rate functions (SFRFs) compare with each other, and with predictions from state-of-the-art theoretical models of
galaxy formation and
evolution. We derive the IR-SFRF from the ALMA A$^3$COSMOS survey, by converting the IR luminosity functions (IR-LFs) into SFRF after correcting for AGN contribution. Similarly, we obtain the UV SFRFs from literature UV LFs, corrected for
dust-extinction. First, we fit the two SFRFs independently via a MCMC approach, then we combine them to obtain the first estimate of the total SFRF out to $z \sim 6$. Finally, we compare this SFRF with the predictions of a set of theoretical models. We derived the UV (
dust-extinction corrected, from literature UV-LFs) and IR SFRFs (from Herschel and ALMA IR-LFs) at $0.5 < z < 6$ , finding that they are mostly complementary, covering different ranges in
star formation rate (SFR$ < 10-100$ M$_{\odot}$yr$^{-1}$ for the UV-corrected and SFR$ > 100$ M$_{\odot}$yr$^{-1}$ for the IR). From the comparison of the total SFRF with model predictions we find an overall good agreement at $z < 2.5$, with increasing difference at higher
redshifts, with all models missing the
galaxies that are forming
stars with the highest SFRs. We finally obtained the UV (
dust-corrected), IR and total
star formation rate densities (SFRDs), finding that there are no
redshift ranges where UV and IR alone are able to reproduce the whole total SFRD.
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All authors A. Traina, C. Gruppioni, I. Delvecchio, B. Magnelli, F. Calura, L. Bisigello, A. Feltre, L. Vallini, G. De Lucia, F. Fontanot, M. Hirschmann, A. Katsianis, M. Parente, O. Cucciati, L. Xie, E. Schinnerer, D. Liu, S. Adscheid, H. S. B. Algera, M. Behiri, F. Gentile, S. Gillman, F. Pozzi, G. Zamorani
Cosmology and Nongalactic Astrophysics
Aletheia: Emulating the non-linear matter power spectrum in the context of evolution mapping
Ariel G. Sanchez, Andrés N. Ruiz, Facundo Rodriguez et al. (+7 more)
We present Aletheia, a new emulator of the non-linear matter power spectrum, $P(k)$, built upon the
evolution mapping framework. This framework addresses the limitations of traditional emulation by focusing on $h$-independent cosmological parameters, which can be separated into those defining the linear power spectrum shape ($\mathbf{\Theta}_{\mathrm{s}}$) and those affecting only its amplitude
evolution ($\mathbf{\Theta}_{\mathrm{e}}$). The combined impact of
evolution parameters and
redshift is compressed into a single amplitude parameter, $\sigma_{12}$. Aletheia uses a two-stage Gaussian Process emulation: a primary emulator predicts the non-linear boost factor as a function of ($\mathbf{\Theta}_{\mathrm{s}}$) and $\sigma_{12}$ for fixed
evolution parameters, while a second one applies a small linear correction based on the integrated growth history. The emulator is trained on shape parameters spanning $\pm$5$\sigma$ of Planck constraints and a wide clustering range $0.2 < \sigma_{12} < 1.0$, providing predictions for $0.006\,{\rm Mpc}^{-1} < k < 2\,{\rm Mpc}^{-1}$. We validate Aletheia against N-body simulations, demonstrating sub-percent accuracy. When tested on a suite of dynamic dark energy models, the full emulator's predictions show a variance of approximately 0.2%, a factor of five smaller than that of the state-of-the-art EuclidEmulator2 (around 1% variance). Furthermore, Aletheia maintains sub-percent accuracy for the best-fit dynamic dark energy cosmology from recent DESI data, a model whose parameters lie outside the training ranges of most conventional emulators. This demonstrates the power of the
evolution mapping approach, providing a robust and extensible tool for precision cosmology.
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All authors Ariel G. Sanchez, Andrés N. Ruiz, Facundo Rodriguez, Carlos Correa, Andrea Fiorilli, Matteo Esposito, Jenny Gonzalez-Jara, Nelson D. Padilla, Alejandro Pérez-Fernández, Sofia Contarini
Astrophysics of Galaxies
Robust galaxy image decompositions with Differential Evolution optimisation and the problem of classical bulges in and beyond the nearby Universe
Dimitri A. Gadotti
Deconstructing
galaxies through two-dimensional decompositions has been shown to be a powerful technique to derive the physical properties of
stellar structures in
galaxies. However, most studies employ fitting
algorithms that are prone to be trapped in local minima, or involve subjective choices. Furthermore, when applied on samples beyond the nearby Universe, results on the fraction of classical bulges in disc
galaxies do not agree with studies on nearby
galaxies. The latter studies point to a small fraction of classical bulges, possibly challenging our merger-driven picture of
galaxy formation. Therefore, understanding the discrepancy between observations in and beyond the nearby Universe is of paramount importance. In this paper, I use a sample of 16 nearby
galaxies drawn from the TIMER project, which previously have been shown to not host classical bulges, and perform decompositions applying different methodologies and employing the original images as well as artificially redshifted images. I show that the Differential
Evolution algorithm is able to provide accurate measurements of structural properties with little subjective intervention, correctly indicating the presence of
nuclear discs (not classical bulges). However, I also show that when the physical spatial resolution is not adequate, a systematic overestimation of the photometric bulge Sérsic index leads to the false conclusion of the presence of classical bulges. I discuss how this may be the root cause of the discrepancy mentioned above, and point out how this issue may be a problem even with data from facilities such as Euclid, HST and JWST.
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High Energy Astrophysical Phenomena
Hierarchical Black Hole Mergers in Nuclear Star Clusters: A Combined Dynamical-Secular Channel for GW231123-like Events
Bin Liu, Dieran Wang and Dong Lai
The recent binary black hole (BH) merger GW231123, with both components likely in the high-mass gap and with high
spins, challenges standard BH binary formation models. It is usually thought that the BHs are of second (or higher) generation (2G), resulting from the mergers of smaller BHs. But the physical processes that produce the merging 2G BH binaries are unclear and highly unconstrained. We show that such 2G mergers can be naturally produced in the
nuclear star cluster of Milky Way-like
galaxy. The dominant channel combines a sequence of binary-single interactions with secular
evolution driven by the central supermassive BH. Our model produces a merger rate consistent with GW231123 and further predicts an abundant population of 2G BH-
star (or low-mass BH) binaries; these binaries may observationally manifest as micro
tidal disruption events or low-frequency gravitational-wave (GW) sources. Detecting these binaries would provide crucial insights into the dynamical pathways of hierarchical BH assembly.
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High Energy Astrophysical Phenomena
Galaxy Mergers Collectively Illuminate the $\gamma$-Ray Sky
Jaya Doliya, Deep Jyoti Das, Subhadip Bouri et al. (+3 more)
The origin and acceleration mechanism of
cosmic rays (CRs) remain fundamental open questions.
Galaxy mergers are proposed as very high-energy CR accelerators, which are expected to produce high-energy (HE) $\gamma$ rays and
neutrinos through interactions with the ambient gas and low-energy background radiation fields. For the first time, we systematically study the HE $\gamma$-ray emission from
galaxy mergers utilising 16.7 years of
Fermi Large Area
Telescope (
Fermi-LAT) data with the sample list compiled from eight survey catalogs. Our analysis finds 8
galaxy mergers that exhibit $\gamma$-ray emission with significance $\gtrsim5\sigma$ in the 1-500 GeV energy range. A stacking analysis of the remaining faint
galaxy mergers yields a combined $\gamma$-ray emission detected at $\sim 35\sigma$ significance, a best-fit spectral index of $\Gamma \approx 2.07$, and an energy flux of $\sim \rm 2\times10^{-14}~erg~cm^{-2}~s^{-1}$. We compare the stacked spectral energy distributions of the
galaxy mergers with the projected sensitivity of the upcoming $\gamma$-ray
telescope Cherenkov
Telescope Array (CTA). Furthermore, we find that 18 previously unassociated
Fermi-LAT sources are spatially coincident with
galaxy mergers. Our findings establish
galaxy mergers as a new class of HE $\gamma$-ray sources. Future
neutrino and $\gamma$-ray observatories will be crucial to discover the particle acceleration mechanism in these newly identified CR sources.
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All authors Jaya Doliya, Deep Jyoti Das, Subhadip Bouri, Pooja Bhattacharjee, Mousumi Das, Ranjan Laha
Astrophysics of Galaxies
A Deep Chandra View of Abell 2597: Bubbles, Shocks, Cold Fueling, and a Plasma Depletion Layer
Osase Omoruyi, Grant Tremblay, Stefi A. Baum et al. (+14 more)
To examine how AGN feedback shapes the intracluster medium (ICM) and fuels black hole
accretion in the cool-core
galaxy cluster Abell 2597, we present deep ($\sim$600 ks) Chandra X-ray observations complemented by archival GMRT
radio and SINFONI near-infrared data.
Radio-mode AGN activity has inflated seven X-ray cavities and driven one to three potential weak shocks ($M \sim 1.05-1.14$) extending to $\sim 150$ kpc, suggesting recurrent outbursts occurring on $\sim 10^7$ year timescales. We also detect a narrow, $\sim$57 kpc X-ray surface brightness deficit-a potential
plasma depletion layer-likely shaped by residual sloshing motions that amplified
magnetic fields and/or displaced gas within the cluster core. Although the AGN injects $\sim 10^{44}$ erg s$^{-1}$ of energy, comparable to the cluster's cooling luminosity, radiative cooling persists at $\sim$15 M$_{\odot} $yr$^{-1}$, replenishing the billion
solar mass cold gas reservoir at the heart of the brightest cluster
galaxy. Sustaining this level of activity requires a continuous fuel supply, yet the estimated Bondi
accretion power ($\sim 2 \times 10^{43}$ erg s$^{-1}$) falls an order of magnitude short of the observed cavity power, suggesting that "hot" gas fueling is insufficient. Instead, archival ALMA observations continue to support a chaotic cold
accretion scenario, where
turbulence-driven condensation fuels the AGN at rates exceeding Bondi
accretion, sustaining a self-regulated feedback cycle that repeatedly shapes the core of Abell 2597.
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All authors Osase Omoruyi, Grant Tremblay, Stefi A. Baum, Tracy E. Clarke, Pratik Dabhade, Andrew Fabian, Massimo Gaspari, Sanna Gulati, Preeti Kharb, Maxim Markevitch, Paul Nulsen, Christopher P. O'Dea, Scott Randall, Somak Raychaudhury, Sravani Vaddi, Alexey Vikhlinin, John Zuhone
Cosmology and Nongalactic Astrophysics · Cross-listed from hep-ph
Stripped-Envelope Supernovae for QCD Axion Detection
Francisco R. Candón, Damiano F. G. Fiorillo, Ángel Gil Muyor et al. (+3 more)
QCD
axions would be copiously produced in the proto-
neutron star formed in a core-collapse
supernova (SN). After escaping, they would convert into gamma rays in the
Galactic magnetic field and, as recently shown, in that of the progenitor
star itself. Here, we show that Type Ibc SNe – whose progenitors have lost their hydrogen or even helium envelopes – are the optimal targets for this search. The stripped progenitors are much more compact, and they show larger
magnetic fields than both red and blue supergiants, the progenitors of Type IIP/L SNe. If the next
galactic SN is of Type Ibc,
Fermi-LAT or a similar gamma-ray satellite might be able to discover the QCD
axion down to masses as small as $m_a\simeq 10^{-4}\,\rm eV$ (Peccei-Quinn scale $f_a\simeq 10^{11} \,\rm GeV$).
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All authors Francisco R. Candón, Damiano F. G. Fiorillo, Ángel Gil Muyor, Hans-Thomas Janka, Georg G. Raffelt, Edoardo Vitagliano
High Energy Astrophysical Phenomena · Cross-listed from hep-ph
Effects of Lighter-than-QCD Axions on Neutron Star Tidal Deformability
Yonatan Kahn, Michael Wentzel and Nicolás Yunes
Finite density corrections to the lighter-than-QCD
axion can invert the effective
axion potential, sourcing a non-trivial
axion field inside dense objects. We perform the first numerical study of the complete dynamics of the lighter-than-QCD
axion in a
neutron star in 1+1 general relativity, extending the region of analysis to low-mass
axions with kilometer-scale Compton wavelengths. We calculate gravitational effects of the
axion field on the
neutron star and show that for a broad range of
axion masses and decay constants,
neutron star properties, such as the mass, radius, and compactness, are affected at the order-1 level. This result indicates that approximate universal
tidal deformability-compactness relation for
neutron stars is non-trivially broken and can serve as a probe of lighter-than-QCD
axions, independent of the unknown
nuclear equation of state. We comment on the potential for
axion studies with future gravitational-wave observations of
neutron stars and applications of this work to other new physics signatures.
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Astrophysics of Galaxies
Steady-State or Not? The Evolution of Cosmic Ray Electron Spectra in Galaxies
Maria Werhahn, Christoph Pfrommer, Joseph Whittingham et al. (+4 more)
Cosmic ray (CR) electrons are key tracers of non-thermal processes in
galaxies, yet their spectra are often modelled under the untested assumption of steady state between injection and cooling. In this work, we present a time-dependent modelling of CR electron spectra in a
galactic context using the CREST code, applied to magnetohydrodynamical simulations of an isolated Milky Way-mass
galaxy performed with AREPO. CR electrons are injected at
supernova sites and evolved with adiabatic changes and cooling processes on Lagrangian tracer particles, including losses from synchrotron, inverse Compton, bremsstrahlung, and Coulomb interactions. We compare these fully time-dependent spectra to local and global steady-state models computed with CRAYON+, as well as to one-zone analytic steady-state solutions. We find that the global CR electron spectrum in the simulated
galactic disk closely resembles a steady-state solution up to energies of 500 GeV, with deviations only at higher energies where cooling times become shorter than injection timescales. High-energy electrons are dominated by recently injected populations that have not yet reached
equilibrium, however, producing a steeper spectrum and lower normalisation than a steady-state model predicts. Spatially, the electrons modelled on-the-fly with CREST are more confined to the
star-forming disk, in contrast to the more extended distributions from steady-state post-processing models. Our results demonstrate that while steady-state assumptions capture the bulk CR electron population in
star-forming disks, a time-dependent treatment is essential to describe the high-energy and outflowing components.
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All authors Maria Werhahn, Christoph Pfrommer, Joseph Whittingham, Léna Jlassi, Rüdiger Pakmor, Philipp Girichidis, Rebekka Bieri
Solar and Stellar Astrophysics
Benjamin K. Capistrant and Jason Dittmann
M
dwarfs are magnetically active
stars that frequently produce
flares, which have implications for both
stellar evolution and
exoplanet studies.
Flare occurrence rates and activity levels of M
dwarfs correlate with
stellar characteristics such as age, mass, and rotation period. We search TESS observations of a known active population of M
dwarfs as well as a volume-limited sample of M
dwarfs within 15 parsecs. We detect
flares in the light curves of these
stars, including 276 of 538 M
dwarfs within 15 pc, and calculate cumulative
flare frequency distributions (FFDs) for each
star. Based on flaring behavior, we categorize
stars into relatively higher and lower activity groups and fit power laws to their FFDs to compare the power law exponent ($\alpha$) across activity levels. We find $\alpha =1.99 \pm 0.07$ for the combined FFD of the lower activity M
dwarfs, compared to averages of $\alpha = 1.94 \pm 0.58$ for highly active
stars with 10-100 detected
flares, and $\alpha = 2.03 \pm 0.43$ for those with > 100 detected
flares, suggesting little
evolution in the power law distribution of
flares as M
dwarfs transition from high to low activity states. The uncertainties for the active
star groups reflect the standard deviation of $\alpha$ values across individual
stars within each subset. Because
stellar flares and associated
stellar activity complicate
exoplanet observations, we also examine the subset of M
dwarfs with JWST transmission spectroscopy follow-up observations in Cycles 1-3. The
flares we detect for these targets are consistent with the broader 15 pc sample, providing context for interpreting planetary atmosphere
retrievals from JWST spectra.
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Astrophysics of Galaxies
Statistics Meet Systematics: Resolution of the Massive Early JWST Galaxy Tension
Jay R. Krishnan and Kevork N. Abazajian
The discovery of massive, high
redshift galaxies with the James Webb Space
Telescope (JWST) has been argued to challenge $\Lambda$CDM (cold dark matter): such systems would require extremely rare
halos and
baryon-to-
stellar-mass conversion efficiencies unphysically approaching – or exceeding – $100\%$. If confirmed at
galaxy-formation–forbidden efficiencies, these
galaxies could signal new physics beyond standard cosmological structure formation. We develop a
galaxy model framework that ties the linear power spectrum to the inferred efficiencies of
galaxy growth while incorporating multiple sources of uncertainties in order to test the structure formation models. The sources of error include (i) observational sample variance, (ii) asymmetric scatter induced by the steepness of the high-mass
halo tail, and (iii) systematic uncertainties in
stellar mass estimates. We find that the inferred
star-formation efficiency is largely controlled by systematic uncertainties in the
stellar mass estimates derived from spectral energy distribution modeling of JWST-detected
galaxies. Because of the inherent Eddington-like bias, systematic uncertainties amplify the asymmetry of the scatter, in some cases by orders of magnitude, thereby bringing the inferred efficiencies into closer agreement with expectations from early
galaxy formation models. We also present how these uncertainties can be applied to the inferred UV luminosity function. Our framework can be used to test $\Lambda$CDM as errors are reduced and further detections are made.
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Solar and Stellar Astrophysics
The physical properties of post-mass-transfer binaries
Rhys Seeburger, Hans-Walter Rix, Kareem El-Badry et al. (+4 more)
Aims. We present and analyse the detailed physical properties of six binary
stellar systems, originally proposed as possible
star-black hole binaries on the basis of radial velocities from
Gaia's third data release, but soon recognised as likely post-mass-transfer binary systems with stripped companions. Methods. We used multi-epoch high-resolution FEROS spectra and spectral disentangling paired with
stellar templates to derive effective temperatures, $T_\mathrm{eff}$;
stellar radii, R*; and projected rotational velocities, v$\sin{i}$ for both components in all systems along with the mass ratio, q = $M_\mathrm{accretor}/M_\mathrm{donor}$ and the components' flux ratio as a function of wavelength. Results. Our analysis directly confirms that all systems are post-mass-transfer binaries with two luminous
stars, i.e. no black hole companions. Each system contains an A-type accretor component that is rapidly rotating and a cooler very low-mass donor (~ 0.25M$\odot$) that is overluminous. Five of the systems show no trace of any emission lines, implying that there is no current mass transfer, consistent with our inferred radii, in all cases within the Roche volume. The data are generally consistent with stable case AB mass transfer with $\beta$ (the fraction of mass lost from the accretor) less than 0.7. While the accretor components rotate rapidly, they rotate well below the critical rotation rate, $v_\mathrm{crit}$, even though there must have been enough mass transfer to
spin them up to a significant fraction of $v_\mathrm{crit}$, according to theoretical models of angular momentum transfer. As neither
magnetic braking nor
tidal synchronisation should have been effective in spinning down the
stars, our results suggest that either mass
accretion does not increase the angular momentum of the accretors to their critical values or the systems never reached these values in the first place.
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All authors Rhys Seeburger, Hans-Walter Rix, Kareem El-Badry, Johanna Müller-Horn, Alex J. Dimoff, Jan Henneco, Jaime I. Villaseñor
High Energy Astrophysical Phenomena
The hard ultraluminous state of NGC 5055 ULX X-1
N. Cruz-Sanchez, E. A. Saavedra, F. A. Fogantini et al. (+2 more)
We present the results of the first broadband X-ray analysis of the ultraluminous X-ray source NGC 5055 ULX X-1, combining simultaneous data from XMM$-$Newton and NuSTAR missions, with a combined exposure time of $\sim$100 ks across the $0.3-20$ keV energy range. The source exhibits a stable flux across the entire exposure with no detectable pulsations by any instrument on their X-ray light curves, placing pulsed-fraction upper limits of 10% and 32% for XMM$-$Newton and NuSTAR, respectively. The X-ray spectrum is dominated by two thermal components consistent with the emission from an
accretion disk, and shows a weak high-energy tail above 10 keV, with no statistical requirement for an additional nonthermal component. The unabsorbed $0.3-20$ keV luminosity is ${\sim}2\times10^{40}$ erg s$^{-1}$, evidencing the ULX nature of the source. The parameters obtained from spectral modeling are consistent with the hard ultraluminous state. Despite the fact that a
neutron-
star accretor cannot be ruled out by the available data, under the assumption that the compact object in NGC 5055 ULX X-1 is a black hole accreting through a geometrically thick, radiation-pressure-supported disk that drives an optically thick wind, we constrained its putative mass to $11-26$ M$_{\odot}$.
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All authors N. Cruz-Sanchez, E. A. Saavedra, F. A. Fogantini, F. García, J. A. Combi
Cosmology and Nongalactic Astrophysics
Investigating the Dark Energy Constraint from Strongly Lensed AGN at LSST-Scale
Sydney Erickson, Martin Millon, Padmavathi Venkatraman et al. (+12 more)
Strongly lensed Active
Galactic Nuclei (AGN) with an observable time delay can be used to constrain the expansion history of the Universe through time-delay cosmography (TDC). As the sample of time-delay lenses grows to statistical size, with $\mathcal{O}$(1000) lensed AGN forecast to be observed by the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST), there is an emerging opportunity to use TDC as an independent probe of dark energy. To take advantage of this statistical sample, we implement a scalable hierarchical inference tool which computes the cosmological likelihood for hundreds of strong lenses simultaneously. With this new technique, we investigate the cosmological constraining power from a simulation of the full LSST sample. We start from individual lenses, and emulate the full joint hierarchical TDC analysis, including image-based modeling, time-delay measurement, velocity dispersion measurement, and external convergence prediction. We fully account for the mass-sheet and mass-anisotropy degeneracies. We assume a sample of 800 lenses, with varying levels of follow-up fidelity based on existing campaigns. With our baseline assumptions, within a flexible $w_0w_a$CDM cosmology, we simultaneously forecast a $\sim$2.5% constraint on H0 and a dark energy figure of merit (DE FOM) of 6.7. We show that by expanding the sample from 50 lenses with IFU kinematics to include 750 lenses with plausible LSST time-delay measurements, we improve the forecasted DE FOM by nearly a factor of 3, demonstrating the value of incorporating this portion of the sample. We also investigate different follow-up campaign strategies, and find significant improvements in the DE FOM with additional
stellar kinematics measurements and higher-precision time-delay measurements. We also demonstrate how the
redshift configuration of time-delay lenses impacts constraining power in $w_0w_a$CDM.
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All authors Sydney Erickson, Martin Millon, Padmavathi Venkatraman, Tian Li, Philip Holloway, Phil Marshall, Anowar Shajib, Simon Birrer, Xiang-Yu Huang, Timo Anguita, Steven Dillmann, Narayan Khadka, Kate Napier, Aaron Roodman, The LSST Dark Energy Science Collaboration
Cosmology and Nongalactic Astrophysics
A model-independent assessment of the late-time dark energy density evolution
Rayff de Souza, Agripino Sousa-Neto, Javier E. González et al. (+1 more)
Combined measurements of
Baryon Acoustic Oscillations (BAO) from the Dark Energy Spectroscopic Survey (DESI), the
Cosmic Microwave Background (CMB) and Type Ia
Supernovae (SN Ia), have recently challenged the $\Lambda$-Cold Dark Matter ($\Lambda$CDM) paradigm, indicating potential evidence for a dynamical dark energy component. These results are usually obtained in the context of the dark energy equation-of-state (EoS) parameterizations, generally implying in phantom-crossing at intermediate
redshifts. However, a general mapping between these parameterizations that yields approximately the same background observables clouds the inference of the true nature of dark energy in the context of these parametric methods. In this work, we propose a model-independent reconstruction of the dark energy density, which is more directly constrained than its EoS, based on the Gaussian Process (GP) regression method with the use of DESI DR2 BAO data and the Pantheon+, Union3 and DESY5 SN Ia samples. In addition, we perform a statistical comparison between the energy densities of $\Lambda$, a non-phantom thawing quintessence-type dark energy, and the Chevallier-Polarski-Linder parameterization with the reconstructed function. We find that all models agree with the GP reconstruction at 95% C.L., with the largest discrepancy coming from $\Lambda$CDM with DESY5 at low
redshifts. Even in this case, our findings suggest that it may be premature to claim statistically significant evidence for evolving or phantom dark energy with current DESI and SN Ia measurements.
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All authors Rayff de Souza, Agripino Sousa-Neto, Javier E. González, Jailson Alcaniz
Astrophysics of Galaxies
High-resolution radio imaging of TGSSJ1530+1049, a radio galaxy in a dense environment at z=4
K. É. Gabányi, S. Frey, L. I. Gurvits et al. (+10 more)
High-
redshift radio galaxies can provide insights into the structure formation and
galaxy evolution at earlier cosmological epochs. TGSSJ1530+1049 was selected as a candidate high-
redshift radio galaxy. Subsequent observations with the James Webb Space
Telescope (JWST) presented in a companion paper (Saxena et al., 2026) have shown that it is located at a
redshift z=4.0. The JWST data furthermore showed that the
radio source is part of one of the densest structures of
galaxies and ionized gas known at these
redshifts. The complex system qualitatively resembles a massive (cluster)
galaxy forming early through a rapid succession of mergers. TGSSJ1530+1049 is an unresolved source down to ~0.6" scale in multiple
radio surveys. To reveal its high-resolution
radio structure and allow for a detailed comparison with JWST observations, we studied its morphology at various angular scales with different
radio interferometric instruments. We observed TGSSJ1530+1049 at milliarcsecond (mas) scale angular resolution with the European VLBI Network (EVN), and at ~100-mas scale resolution with the enhanced Multi-Element Remotely Linked Interferometer Network (e-MERLIN). We recovered a complex north–south oriented structure with steep-spectrum
radio-emitting features, which are associated with lobes and hot spots of a jetted active
galactic nucleus. The centre of the
radio galaxy proved to be too faint at cm wavelengths to be unambiguously detected in our observations. Nevertheless, the linear size (~5.5 kpc) and the
radio power place it among the so-called medium-sized symmetric objects, a smaller and/or confined version of larger
radio galaxies. Comparison between the
radio morphology and that of the ionized gas observed by JWST shows that the two are closely aligned. However, the optical emission line gas extends out to ~25 kpc, which is well beyond the detected
radio structures. (Abridged)
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All authors K. É. Gabányi, S. Frey, L. I. Gurvits, Z. Paragi, K. Perger, A. Saxena, R. A. Overzier, M. Villar-Martín, V. Reynaldi, G. Miley, H. J. A. Röttgering, A. Humphrey, Gy. Mező
Astrophysics of Galaxies
JWST observes the assembly of a massive galaxy at z~4
Aayush Saxena, Roderik A. Overzier, Catarina Aydar et al. (+18 more)
We present JWST observations of the
radio galaxy TGSSJ1530+1049, spectroscopically confirmed at $z=4.0$. NIRCam images and NIRSpec/IFU spectroscopy (R=2700) show that TGSSJ1530+1049 is part of one of the densest-known structures of continuum and line-emitting objects found at these
redshifts. NIRCam images show a number of distinct continuum objects and evidence of interactions traced by diffuse emission, and the NIRSpec IFU cube reveals further strong line emitting regions. We identify six continuum and four additional strong H$\alpha$ emitting sources with weaker or no underlying continuum within the 3x3 arcsec IFU field. From spatial
alignment with high-resolution
radio data and emission line profiles, the
radio AGN host
galaxy is clearly identified. The bright H$\alpha$ emission (but not the optical components) is distributed remarkably linearly along the
radio axis, suggestive of a biconical illumination zone by a central obscured AGN. The emission line kinematics indicate jet-gas interactions on scales of a few kpc. However, due to large relative velocities and presence of underlying continuum, the
alignment with the
radio structure appears to be, at least partly, caused by a particular configuration of interacting
galaxies. At least four objects within a 10x10 (projected) kpc$^2$ area which includes the
radio source have high
stellar masses ($\log(M_\star/M_\odot)>10.3$) and
star formation rates in the range $70-163\,M_\odot$ yr$^{-1}$. Using a
stellar mass-based analysis, we predict a total dark matter
halo mass of $\approx10^{13} M_\odot$. Based on the physical separations and velocity differences between the
galaxies, it is expected that these
galaxies will merge to form a massive
galaxy within a few Gyr. The system qualitatively resembles the forming brightest cluster
galaxies in cosmological simulations that form early through a rapid succession of mergers.
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All authors Aayush Saxena, Roderik A. Overzier, Catarina Aydar, Jianwei Lyu, George H. Rieke, Victoria Reynaldi, Montserrat Villar-Martín, Krisztina Éva Gabányi, Kenneth J. Duncan, Sándor Frey, Andrew Humphrey, George Miley, Laura Pentericci, Krisztina Perger, Huub Röttgering, Philip Best, Sarah E. I. Bosman, Gyorgy Mező, Masafusa Onoue, Zsolt Paragi, Bram Venemans
High Energy Astrophysical Phenomena · Cross-listed from gr-qc
Coupling between gravitational and electromagnetic perturbations on Kerr Spacetime
Fawzi Aly and Dejan Stojkovic
We extend our previous Schwarzschild metric-based studies of gravitational–electromagnetic (GEM) coupling to rotating black holes by working directly in a
curvature-based Newman–Penrose/Teukolsky framework on Kerr spacetime. Within a minimally coupled Einstein–Maxwell system, we derive explicit quadratic electromagnetic source terms for the
spin-$-2$ Teukolsky equation, providing a foundation for future numerical studies of GEM interactions in the framework of black-hole spectroscopy. Moreover, we give order-of-magnitude arguments showing that GEM quadratic quasinormal modes (QQNMs) can become relevant in a range of charged and magnetized astrophysical scenarios. Finally, we show through a brief dilaton-theory example that the GEM QQNM spectrum is sensitive to how
gravity couples to electromagnetism, thereby providing a model-based way to test minimal coupling and to constrain hidden $U(1)$ sectors with gravitational-wave observations.
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Astrophysics of Galaxies
Sense and Sensitivity - I. Uncertainty analysis of the gas-phase chemistry in AGB outflows
M. Van de Sande, M. Gueguen, T. Danilovich et al. (+1 more)
Chemical reaction networks are central to all chemical models. Each rate coefficient has an associated uncertainty, which is generally not taken into account when calculating the chemistry. We performed the first uncertainty analysis of a chemical model of C-rich and O-rich AGB
outflows using the Rate22 reaction network. Quantifying the error on the model predictions enables us to determine the need for adding complexity to the model. Using a Monte Carlo sampling method, we quantified the impact of the uncertainties on the chemical kinetic data on the predicted fractional abundances and column densities. The errors are caused by a complex interplay of reactions forming and destroying each species. Parent species show an error on their envelope sizes, which is not caused by the uncertainty on their photodissociation rate, but rather the chemistry reforming the parent after its photodissociation. Using photodissociation models to estimate the envelope size might be an oversimplification. The error on the CO envelope impacts retrieved mass-loss rates by up to a factor of two. For daughter species, the error on the peak fractional abundance ranges from a factor of a few to three orders of magnitude, and is on average about 10% of its value. This error is positively correlated with the error on the column density. The standard model suffices for many species, e.g., the radial distribution of cyanopolyynes and hydrocarbon radicals around IRC +10216. However, including spherical asymmetries,
dust-gas chemistry, and photochemistry induced by a close-by
stellar companion are still necessary to explain certain observations.
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All authors M. Van de Sande, M. Gueguen, T. Danilovich, T.J. Millar
High Energy Astrophysical Phenomena
Multi Messenger Study of GRB 221009A with VHE Gamma-ray and Neutrino Afterglow from a Gaussian Structured Jet
T. Mondal, S. Razzaque, Jagdish C. Joshi et al. (+2 more)
Recent detections of very-high-energy (VHE; $\gtrsim 100~{\rm GeV}$) emission from GRB afterglows, most notably the unprecedented brightness of GRB~221009A observed by LHAASO, reveal components beyond the standard electron synchrotron model. The multi-TeV
photons motivate synchrotron self-Compton and possible hadronic contributions, while the non-detection of coincident
neutrinos by IceCube/KM3NeT/GRAND200k constrains the microphysical parameters, jet kinetic energy, and ambient-medium density. We model the VHE afterglow of GRB~221009A with an external forward shock from a Gaussian structured jet in a uniform-density medium. This angular structure reproduces the extreme TeV output at an off-axis angle but without demanding large energies as in a top-hat jet. We compute the corresponding $p\gamma$
neutrino flux in the PeV-EeV range and derive a time-integrated upper limit using the effective areas of IceCube-Gen2 and GRAND200k. This provides insight into the contribution of individual GRBs to
neutrino events. The predicted
neutrino flux for GRB~221009A, using parameters inferred from the multi-wavelength spectral energy distribution, lies below the sensitivities of these detectors. Even our correlation analysis, optimized for
neutrino searches with the upcoming GRAND200k, indicates that the expected number of events from this GRB is of order $\sim 0.1$ under a highly optimistic microphysical parameter regime. We also compare
neutrino-flux variations from on-axis and off-axis viewing geometries and find an approximately order of magnitude difference in the signal. Thus, our study concludes that a brighter burst closer than GRB~221009A would be crucial for
neutrino detection by upcoming
telescopes. Future GRB detections by the Cherenkov
Telescope Array will provide important constraints on their geometry, radiation mechanisms, and possible associated
neutrino signals.
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All authors T. Mondal, S. Razzaque, Jagdish C. Joshi, S. Majumder, D. Bose
Instrumentation and Methods for Astrophysics · Cross-listed from physics.ins-det
Variable-temperature attenuator calibration method for on-wafer microwave noise characterization of low-noise amplifiers
Anthony J. Ardizzi, Jiayin Zhang, Akim A. Babenko et al. (+2 more)
Low-noise cryogenic microwave amplifiers are widely used in applications such as
radio astronomy and
quantum computing. On-wafer noise characterization of cryogenic low-noise transistors is desirable because it facilitates more rapid characterization of devices prior to packaging, but obtaining accurate noise measurements is difficult due to the uncertainty arising from the input loss and temperature gradients prior to the device-under-test (DUT). Here, we report a calibration method that enables the simultaneous determination of the backend noise temperature and effective-noise-ratio at the input plane of the DUT. The method is based on measuring the S-parameters and noise power of a series of attenuators at two or more distinct physical temperatures. We validate our method by measuring the noise temperature of InP HEMTs in 4-8 GHz. The calibration method can be generalized to measure the microwave noise temperature of any two-port device so long as a series of attenuators can be measured at two or more distinct physical temperatures.
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All authors Anthony J. Ardizzi, Jiayin Zhang, Akim A. Babenko, Kieran A. Cleary, Austin J. Minnich
Solar and Stellar Astrophysics
Statistical analysis of eclipsing binaries with monotonic orbital-period variations: A-type W UMa contact systems
Shinjirou Kouzuma
On the basis of monotonic orbital-period variations, this study aims to identify genuine relationships between binary parameters and the rates of mass transfer (MT), mass loss (ML), and angular momentum loss (AML). Sample binaries with monotonic period variations are collected from the literature, together with well-determined binary parameters. Assuming the monotonic variations are responsible for any one of the MT, ML, and AML, their rates are calculated with the rates of change of period. After selecting crucial parameters using partial least-squares analysis, a parameter that exhibits the closest correlation with any one of the derived rates is further selected using partial regression plots. Moreover, power-law relationships are found for the discovered correlations. The properties of the sample binaries are also investigated by examining associations between binary parameters. In the systems with negative period variations, it is found that the rate of MT from more- to less-massive
stars is a function of the primary radius; the AML rate is a function of the fill-out factor. In addition, the relationships between the mass ratio and
stellar masses indicate that the ML rate relative to the MT rate decreases with increasing mass ratio below ~0.46. Meanwhile, in the systems with positive variations, it is found that the rate of MT from less- to more-massive
stars is a function of the luminosity ratio and/or mass ratio; the ML rate is a function of the secondary temperature. The discussion also addresses possible processes occurring in the sample binaries.
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Solar and Stellar Astrophysics
High-Precision Multi-Period Analysis of the Ellipsoidal Variable Candidate TIC~470127886 from TESS Photometry
Roo Weerasinghe
We present the first detailed photometric characterization of TIC 470127886, a previously unstudied multi-periodic variable
star discovered in TESS photometry. Analysis of 145,374 high-cadence observations spanning 696 days (944-day baseline, 2023 January-2024 October) across 10 sectors (60, 59, 58, 53, 52, 73, 86, 79, 78, 85) reveals complex periodic variability with a primary period of 5.544527 +/- 0.004307 days and false alarm probability 1.47 x 10^-87. Lomb-Scargle analysis identifies three significant periods at 5.545, 5.801, and 8.874 days with amplitudes of 15,702, 12,772, and 12,670 ppm. The phase-folded light curve shows smooth, sinusoidal morphology consistent with ellipsoidal variation from
tidal distortion in a close binary, with no eclipse features. A three-component sinusoidal model, appropriate for ellipsoidal variables, provides excellent fit quality. Validation tests confirm signal authenticity and persistence, and systematic checks verify no contamination from nearby
stars (>3 mag fainter). We classify TIC 470127886 as an ellipsoidal variable candidate with 0.70 confidence, with multi-period behavior suggesting additional variability mechanisms beyond
tidal distortion. This work demonstrates high-precision characterization of complex multi-periodic variables in TESS photometry.
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Astrophysics of Galaxies
A Fleeting GLIMPSE of N/O Enrichment at Cosmic Dawn: Evidence for Wolf Rayet N Stars in a z = 6.1 Galaxy
Danielle A. Berg, Rohan P. Naidu, John Chisholm et al. (+18 more)
We present the discovery of extreme nitrogen enrichment by Wolf Rayet nitrogen
stars (WN) in the metal-poor (~10% Z_odot), lensed, compact (R_eff ~ 20 pc)
galaxy RXCJ2248 at z=6.1, revealed by unprecedentedly deep JWST/NIRSpec medium-resolution spectroscopy from the GLIMPSE-D Survey. The exquisite S/N reveals multiple high-ionization nebular lines and broad Balmer and [OIII] components (FWHM~700-3000 km/s). We detect broadened HeII 1640 and 4687 (FWHM~530 km/s) and strong NIII] 4642 emission consistent with a population of WN
stars, making RXCJ2248 the most distant
galaxy with confirmed WR features to date. We measure the multi-phase nebular density across five ions, the direct-method
metallicity (12+log(O/H)= 7.749+/-0.023), and a non-uniform elemental enrichment pattern of extreme N/O enhancement (log(N/O)=-0.390+/-0.035 from N^+, N^+2, and N^+3) and suppressed C/O relative to empirical C/N trends. We show that this abundance pattern can be explained by enrichment from a dual-burst with a low WC/WN ratio, as expected at low
metallicities. Crucially, these signatures can only arise during a brief, rare evolutionary window shortly after a burst (~3-6 Myr), when WN
stars dominate chemical feedback but before dilution by later yields (e.g.,
supernovae). The observed frequency of strong N emitters at high-z implies a ~50 Myr burst duty cycle, suggesting that N/O outliers may represent a brief but ubiquitous phase in the
evolution of highly
star-forming early
galaxies. The detection in RXCJ2248, therefore, provides the first direct evidence of WN-driven chemical enrichment in the early Universe and a novel timing argument for the bursty
star formation cycles that shaped
galaxies at
cosmic dawn.
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All authors Danielle A. Berg, Rohan P. Naidu, John Chisholm, Hakim Atek, Seiji Fujimoto, Vasily Kokorev, Lukas J. Furtak, Chiaki Kobayashi, Daniel Schaerer, Angela Adamo, Qinyue Fei, Damien Korber, Jorryt Matthee, Rui Marques-Chaves, Zorayda Martinez, Kristen B. W. Mcquinn, Julian B. Muñoz, Pascal A. Oesch, Daniel P. Stark, Mabel G. Stephenson, Tiger Yu-Yang Hsiao
Astrophysics of Galaxies
High Resolution Observations of CO(3-2) in Haro 2: Cool Molecular Outflows of a Ly$\alpha$ Emitter
Sara Beck, Pei-Ying Hsieh and Jean Turner
Haro 2 is a blue compact
dwarf galaxy and the closest (at 21Mpc) known $Ly\alpha$ emitter. UV and optical observations have found Haro 2 to be immersed in shells of partly ionized gas expanding at $\sim200$km/s. Observations of CO(2-1) (Becket et al 2020; Paper 1) with moderate ($2^{\prime\prime}$) resolution discovered a large-scale one-sided
outflow associated with a soft X-ray bubble and apparently driven by the young
star clusters created in the recent starburst. We present here SMA observations of CO(3-2) with $1.1^{\prime\prime}$ resolution in Haro 2. The opposite-side component of the large molecular
outflow is detected lying in the direction of the fast ionized
outflow; it is very confined in area. An additional
outflow is apparent in the CO(3-2); it is south-east of the
galaxy in a region holding weak
star formation and a moderate-luminosity hard X-ray source. All the molecular
outflow and filament velocities are within $\lesssim\pm50$km/s of the systemic velocity of the
galaxy.
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Cosmology and Nongalactic Astrophysics · Cross-listed from gr-qc
Bimodular Gravity: Vacuum Evolution with a Frame-Dependent Phantom Crossing
James Hallam and João Magueijo
Unimodular
gravity recasts the cosmological constant as an integration constant, fixed by a constraint on the volume element rather than chosen in the action. We ask what becomes of this constant when matter couples not to the gravitational metric, but to a second metric disformally related to it through a scalar field. Imposing a volume constraint on each metric, we find a theory in which the scalar does not propagate, yet still drives a non-trivial expansion. Written as a single-metric theory, its kinetic term is fixed to a prescribed function of spacetime, and the cosmological constant is replaced by a
vacuum contribution that need not be constant. Moreover, we find that this theory admits a phantom crossing through a purely frame-dependent mechanism. This construction, however, rests on a feature invisible with a single metric, and unimodular formalisms that are classically equivalent in that case cease to agree once there are two disformally related metrics.
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Cosmology and Nongalactic Astrophysics · Cross-listed from physics.hist-ph
The Birth of Gravitational Particle Creation: the Enduring Legacy of Leonard Parker's 1966 Thesis
Antonio Ferreiro, Jose Navarro-Salas and Silvia Pla
This paper offers a historical overview of the origins and enduring significance of gravitational particle creation, a groundbreaking discovery first formulated in Leonard Parker's 1966 doctoral thesis at Harvard University. By tracing the context in which Parker developed this idea and examining its subsequent influence, the paper highlights how the concept of gravitational particle creation advanced the study of
quantum field theory in curved spacetime and profoundly shaped modern cosmology, as well as the
quantum theory of black holes.
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Earth and Planetary Astrophysics
The bulk metal content of WASP-80 b from joint interior-atmosphere retrievals: Breaking degeneracies and exploring biases with panchromatic spectra
Lorena Acuña-Aguirre, Laura Kreidberg, Paul Mollière et al. (+1 more)
WASP-80 b is an unusually low-density
exoplanet in tension with the metal-rich composition expected for a
planet of its mass. We aim to derive precise constraints on WASP-80 b's bulk metal mass fraction, atmospheric composition, and thermal structure. We conducted a suite of
retrievals using three approaches: traditional interior-only, atmosphere-only, and joint interior-atmosphere
retrievals. We coupled the open-source models GASTLI and petitRADTRANS, which describe planetary structure and thermal
evolution, and atmospheric chemistry and clouds, respectively. Our
retrievals combine mass and age with panchromatic spectra from JWST and HST in both transmission (0.5-4 $\mu$m) and emission (1-12 $\mu$m) as observational constraints. We identify two fiducial scenarios. In the first, WASP-80 b has an internal temperature consistent with its age in the absence of external heating sources, and its atmosphere is in chemical
equilibrium, with an atmospheric
metallicity M/H = 2.75$^{+0.88}_{-0.56}$x
solar, a bulk metal mass fraction $Z_{planet}=0.12\pm0.02$, and a core mass $M_{core}=3.49^{+3.49}_{-1.59} \ M_{\oplus}$. In the second scenario, WASP-80 b may be inflated by an additional heat source - possibly induced by
magnetic fields - with an atmospheric
metallicity M/H = 10.00$^{+8.20}_{-4.75}$x
solar, $Z_{planet}=0.28\pm0.11$, and $M_{core}=31.8^{+21.3}_{-17.5} \ M_{\oplus}$. The super-
solar M/H and sub-
solar C/O ratios in both scenarios suggest late pebble or planetesimal
accretion, while additional heating is required to reconcile the data with the more massive core predicted by the core
accretion paradigm. In general, joint
retrievals are inherently affected by a degeneracy between atmospheric chemistry and internal structure. Together with flexible cloud treatment and an unweighted likelihood, this leads to larger uncertainties in bulk and atmospheric compositions than previously claimed.
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All authors Lorena Acuña-Aguirre, Laura Kreidberg, Paul Mollière, Nora Bachmann