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- ID:
- ivo://CDS.VizieR/J/ApJS/199/22
- Title:
- UV to far-IR photometry of galaxies
- Short Name:
- J/ApJS/199/22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present a sample of cluster galaxies devoted to study the environmental influence on the star formation activity. This sample of galaxies inhabits in clusters showing a rich variety in their characteristics and have been observed by the SDSS-DR6 down to M_B_~-18, and by the Galaxy Evolution Explorer AIS throughout sky regions corresponding to several megaparsecs. We assign the broadband and emission-line fluxes from ultraviolet to far-infrared to each galaxy performing an accurate spectral energy distribution for spectral fitting analysis. The clusters follow the general X-ray luminosity versus velocity dispersion trend of L_X_{propto}{sigma}^4.4^_c_.
- ID:
- ivo://CDS.VizieR/J/ApJS/143/377
- Title:
- UV-to-FIR magnitudes for 83 starburst galaxies
- Short Name:
- J/ApJS/143/377
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a database of UV-to-FIR data of 83 nearby starburst galaxies. The galaxies are selected based upon the availability of IUE data. We have recalibrated the IUE UV spectra for these galaxies by incorporating the most recent improvements. For 45 of these galaxies we use observations by Storchi-Bergmann et al. (1995ApJS...98..103S) and McQuade et al. (1995ApJS...97..331M) for the spectra in the optical range. The NIR data are from new observations obtained at the NASA/IRTF and the Mount Laguna Observatory, combined with the published results from observations at the Kitt Peak National Observatory. In addition, published calibrated ISO data are included to provide mid-IR flux densities for some of the galaxies. The optical-to-IR data are matched as closely as possible to the IUE large aperture. In conjunction with IRAS and ISO FIR flux densities, all these data form a set of observed spectral energy distributions (SEDs) of the nuclear regions of nearby starburst galaxies. The SEDs should be useful in studying star formation and dust/gas attenuation in galaxies. We also present the magnitudes in the standard BVRI and various HST/WFPC2 bandpasses synthesized from the UV and optical wavelength ranges of these SEDs. For some of the galaxies, the HST/WFPC2 magnitudes synthesized from the SEDs are checked with those directly measured from WFPC2 images to test the photometric errors of the optical data and their effective matching of apertures with the UV data. The implications of the new SEDs on the star formation rates and dust/gas attenuation are briefly discussed.
- ID:
- ivo://CDS.VizieR/J/A+A/533/A142
- Title:
- UV-to-IR fluxes of Hickson compact groups
- Short Name:
- J/A+A/533/A142
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a comprehensive study on the impact of the environment of compact galaxy groups on the evolution of their members using a multi-wavelength analysis, from the UV to the infrared, for a sample of 32 Hickson compact groups (HCGs) containing 135 galaxies. Fitting the SEDs of all galaxies with the state-of-the-art model of da Cunha (2008MNRAS.388.1595D) we can accurately calculate their mass, SFR, and extinction, as well as estimate their infrared luminosity and dust content. We compare our findings with samples of field galaxies, early-stage interacting pairs, and cluster galaxies with similar data. We find that classifying the groups as dynamically "old" or "young", depending on whether or not at least one quarter of their members are early-type systems, is physical and consistent with past classifications of HCGs based on their atomic gas content. Dynamically "old" groups are more compact and display higher velocity dispersions than "young" groups. Late-type galaxies in dynamically "young" groups have specific star formation rates (sSFRs), NUV-r, and mid-infrared colors which are similar to those of field and early stage interacting pair spirals. Late-type galaxies in dynamically "old" groups have redder NUV-r colors, as they have likely experienced several tidal encounters in the past building up their stellar mass, and display lower sSFRs. We identify several late-type galaxies which have sSFRs and colors similar to those of elliptical galaxies, since they lost part of their gas due to numerous interactions with other group members. Also, 25% of the elliptical galaxies in these groups have bluer UV/optical colors than normal ellipticals in the field, probably due to star formation as they accreted gas from other galaxies of the group, or via merging of dwarf companions. Finally, our SED modeling suggests that in 13 groups, 10 of which are dynamically "old", there is diffuse cold dust in the intragroup medium. All this evidence point to an evolutionary scenario in which the effects of the group environment and the properties of the galaxy members are not instantaneous. Early on, the influence of close companions to group galaxies is similar to the one of galaxy pairs in the field. However, as the time progresses, the effects of tidal torques and minor merging, shape the morphology and star formation history of the group galaxies, leading to an increase of the fraction of early-type members and a rapid built up of the stellar mass in the remaining late-type galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/877/152
- Title:
- UV to NIR light curves of type Ia SN 2017erp
- Short Name:
- J/ApJ/877/152
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present space-based ultraviolet/optical photometry and spectroscopy with the Swift Ultra-Violet/Optical Telescope and Hubble Space Telescope (HST), respectively, along with ground-based optical photometry and spectroscopy and near-infrared spectroscopy of supernova SN 2017erp. The optical light curves and spectra are consistent with a normal SN Ia. Compared to previous photometric samples in the near-ultraviolet (NUV), SN 2017erp has UV colors that are redder than NUV-blue SNe Ia corrected to similar optical colors. The chromatic difference between SNe 2011fe and 2017erp is dominated by the intrinsic differences in the UV rather than the expected dust reddening. This chromatic difference is similar to the SALT2 color law, derived from rest-frame ultraviolet photometry of higher redshift SNe Ia. Differentiating between intrinsic UV diversity and dust reddening can have important consequences for determining cosmological distances with rest-frame ultraviolet photometry. This ultraviolet spectroscopic series is the first from HST of a normal, albeit reddened, NUV-red SN Ia and is important for analyzing SNe Ia with intrinsically redder NUV colors. We show model comparisons suggesting that metallicity could be the physical difference between NUV-blue and NUV-red SNe Ia, with emission peaks from reverse fluorescence near 3000{AA} implying a factor of ~10 higher metallicity in the upper layers of SN 2017erp compared to SN 2011fe. Metallicity estimates are very model dependent, however, and there are multiple effects in the UV. Further models and UV spectra of SNe Ia are needed to explore the diversity of SNe Ia, which show seemingly independent differences in the near-UV peaks and mid-UV flux levels.
- ID:
- ivo://CDS.VizieR/J/ApJ/898/166
- Title:
- UV to NIR obs. of SN 2019ehk
- Short Name:
- J/ApJ/898/166
- Date:
- 21 Mar 2022 09:18:33
- Publisher:
- CDS
- Description:
- We present panchromatic observations and modeling of the Calcium-rich supernova (SN) 2019ehk in the star-forming galaxy M100 (d~16.2Mpc) starting 10hr after explosion and continuing for ~300days. SN 2019ehk shows a double-peaked optical light curve peaking at t=3 and 15days. The first peak is coincident with luminous, rapidly decaying Swift-XRT-discovered X-ray emission (L_x_~10^41^erg/s at 3days; Lx{propto}t^-3^), and a Shane/Kast spectral detection of narrow H{alpha} and HeII emission lines (v~500km/s) originating from pre-existent circumstellar material (CSM). We attribute this phenomenology to radiation from shock interaction with extended, dense material surrounding the progenitor star at r<10^15^cm and the resulting cooling emission. We calculate a total CSM mass of ~7x10^-3^M_{sun}_ (M_He_/M_H_~6) with particle density n~10^9^cm^-3^. Radio observations indicate a significantly lower density n<10^4^cm^-3^ at larger radii r>(0.1-1)x10^17^cm. The photometric and spectroscopic properties during the second light-curve peak are consistent with those of Ca-rich transients (rise-time of t_r_=13.4!+/-0.210days and a peak B-band magnitude of M_B_=-15.1+/-0.200mag). We find that SN 2019ehk synthesized (3.1+/-0.11)x10^-2^M_{sun}_ of ^56^Ni and ejected M_ej_=(0.72+/-0.040)M_{sun}_ total with a kinetic energy E_k_=(1.8+/-0.10)x10^50^erg. Finally, deep HST pre-explosion imaging at the SN site constrains the parameter space of viable stellar progenitors to massive stars in the lowest mass bin (~10M_{sun}_) in binaries that lost most of their He envelope or white dwarfs (WDs). The explosion and environment properties of SN 2019ehk further restrict the potential WD progenitor systems to low-mass hybrid HeCO WD+CO WD binaries.
- ID:
- ivo://CDS.VizieR/J/ApJ/902/6
- Title:
- UV to visible-light observations of SN 2018fif
- Short Name:
- J/ApJ/902/6
- Date:
- 25 Feb 2022 11:02:29
- Publisher:
- CDS
- Description:
- High-cadence transient surveys are able to capture supernovae closer to their first light than ever before. Applying analytical models to such early emission, we can constrain the progenitor stars' properties. In this paper, we present observations of SN 2018fif (ZTF18abokyfk). The supernova was discovered close to first light and monitored by the Zwicky Transient Facility (ZTF) and the Neil Gehrels Swift Observatory. Early spectroscopic observations suggest that the progenitor of SN 2018fif was surrounded by relatively small amounts of circumstellar material compared to all previous cases. This particularity, coupled with the high-cadence multiple-band coverage, makes it a good candidate to investigate using shock-cooling models. We employ the SOPRANOS code, an implementation of the model by Sapir & Waxman and its extension to early times by Morag et al. Compared with previous implementations, SOPRANOS has the advantage of including a careful account of the limited temporal validity domain of the shock-cooling model as well as allowing usage of the entirety of the early UV data. We find that the progenitor of SN 2018fif was a large red supergiant with a radius of R=744.0_-128.0_^+183.0^R_{sun}_ and an ejected mass of M_ej_=9.3_-5.8_^+0.4^M_{sun}_. Our model also gives information on the explosion epoch, the progenitor's inner structure, the shock velocity, and the extinction. The distribution of radii is double- peaked, with smaller radii corresponding to lower values of the extinction, earlier recombination times, and a better match to the early UV data. If these correlations persist in future objects, denser spectroscopic monitoring constraining the time of recombination, as well as accurate UV observations (e.g., with ULTRASAT), will help break the extinction/radius degeneracy and independently determine both.
- ID:
- ivo://CDS.VizieR/J/AJ/140/1137
- Title:
- UV, VIH photometry of NGC 1311
- Short Name:
- J/AJ/140/1137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have extracted point-spread-function-fitted stellar photometry from near-ultraviolet, optical, and near-infrared images, obtained with the Hubble Space Telescope, of the nearby (D~5.5Mpc) SBm galaxy NGC 1311. The ultraviolet and optical data reveal a population of hot main-sequence (MS) stars with ages of 2-10Myr. We also find populations of blue supergiants with ages between 10 and 40Myr and red supergiants with ages between 10 and 100Myr.
- ID:
- ivo://CDS.VizieR/J/ApJ/899/128
- Title:
- Validated & new members of NGC 7000/IC 5070 Complex
- Short Name:
- J/ApJ/899/128
- Date:
- 14 Mar 2022 07:05:45
- Publisher:
- CDS
- Description:
- We examine the clustering and kinematics of young stellar objects (YSOs) in the North America/Pelican Nebulae, as revealed by Gaia astrometry, in relation to the structure and motions of the molecular gas, as indicated in molecular-line maps. The Gaia parallaxes and proper motions allow us to significantly refine previously published lists of YSOs, demonstrating that many of the objects previously thought to form a distributed population turn out to be nonmembers. The members are subdivided into at least six spatio-kinematic groups, each of which is associated with its own molecular cloud component or components. Three of the groups are expanding, with velocity gradients of 0.3-0.5km/s/pc, up to maximum velocities of ~8km/s away from the groups' centers. The two known O-type stars associated with the region, 2MASS J20555125+4352246 and HD 199579, are rapidly escaping one of these groups, following the same position-velocity relation as the low-mass stars. We calculate that a combination of gas expulsion and tidal forces from the clumpy distribution of molecular gas could impart the observed velocity gradients within the groups. However, on a global scale, the relative motions of the groups do not appear either divergent or convergent. The velocity dispersion of the whole system is consistent with the kinetic energy gained due to gravitational collapse of the complex. Most of the stellar population has ages similar to the freefall timescales for the natal clouds. Thus, we suggest the nearly freefall collapse of a turbulent molecular cloud as the most likely scenario for star formation in this complex.
- ID:
- ivo://CDS.VizieR/V/151
- Title:
- VANDELS High-Redshift Galaxy Evolution
- Short Name:
- V/151
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- VANDELS is a new ESO spectroscopic Public Survey targeting the high-redshift Universe. Exploiting the red sensitivity of the refurbished VIMOS spectrograph, the survey is obtaining ultra-deep optical spectroscopy of around 2100 galaxies in the redshift interval 1.0<z<7.0, with 85% of its targets selected to be at z>=3. The fundamental aim of the survey is to provide the high signal-to-noise spectra necessary to measure key physical properties such as stellar population ages, metallicities and outflow velocities from detailed absorption-line studies. By targeting two extragalactic survey fields with superb multi-wavelength imaging data, VANDELS will produce a unique legacy dataset for exploring the physics underpinning high-redshift galaxy evolution.
