Abstract We present the construction of a deep multiwavelength point-spread-function-matched photometric catalog in the Ultra-Deep Survey (UDS) field following the final UKIDSS UDS release. The catalog includes photometry in 24 filters, from the MegaCam-uS0.38μm band to the Spitzer-IRAC 8μm band, over ∼0.9 deg2and with a 5σdepth of 25.3 AB in theK-band detection image. The catalog, containing ≈188,564 (136,235) galaxies at 0.2 <z< 8.0 with stellar mass andK-band total magnitudeK< 25.2 (24.3) AB, enables a range of extragalactic studies. We also provide photometric redshifts, corresponding redshift probability distributions, and rest-frame absolute magnitudes and colors derived using the template-fitting codeeazy-py. Photometric redshift errors are less than 3%−4% atz< 4 across the full brightness range in theKband and stellar mass range . Stellar population properties (e.g., stellar mass, star formation rate, dust extinction) are derived from the modeling of the spectral energy distributions using the codesFASTand Dense Basis.
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A Model for Eruptive Mass Loss in Massive Stars
Abstract Eruptive mass loss in massive stars is known to occur, but the mechanism(s) are not yet well understood. One proposed physical explanation appeals to opacity-driven super-Eddington luminosities in stellar envelopes. Here, we present a 1D model for eruptive mass loss and implement this model in theMESAstellar evolution code. The model identifies regions in the star where the energy associated with a local super-Eddington luminosity exceeds the binding energy of the overlaying envelope. The material above such regions is ejected from the star. Stars with initial masses of 10−100M⊙at solar and SMC metallicities are evolved through core helium burning, with and without this new eruptive mass-loss scheme. We find that eruptive mass loss of up to ∼10−2M⊙yr−1can be driven by this mechanism, and occurs in a vertical band on the H-R diagram between . This predicted eruptive mass loss prevents stars of initial masses ≳20M⊙from evolving to become red supergiants (RSGs), with the stars instead ending their lives as blue supergiants, and offers a possible explanation for the observed lack of RSGs in that mass regime.
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- Award ID(s):
- 2009131
- PAR ID:
- 10549480
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 974
- Issue:
- 2
- ISSN:
- 0004-637X
- Format(s):
- Medium: X Size: Article No. 270
- Size(s):
- Article No. 270
- Sponsoring Org:
- National Science Foundation
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