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- ID:
- ivo://CDS.VizieR/J/MNRAS/411/2009
- Title:
- H narrow-band imaging of XMMU J2235.3-2557
- Short Name:
- J/MNRAS/411/2009
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results of a narrow-band photometric study of the massive galaxy cluster XMMU J2235.3-2557 at z=1.39. We obtained deep H narrow-band imaging with the Near InfraRed Imager and Spectrometer on Gemini North, corresponding to H{alpha} emission at the cluster's redshift. Our sample consists of 82 galaxies within a radius of ~500kpc, 10 of which are spectroscopically confirmed cluster members. 16 galaxies are identified as excess line-emitters.
- ID:
- ivo://CDS.VizieR/J/MNRAS/423/3652
- Title:
- H narrow-band imaging of XMMU J2235.3-2557
- Short Name:
- J/MNRAS/423/3652
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an extended narrow-band H{alpha} study of the massive galaxy cluster XMMU J2235.3-2557 at z=1.39. This paper represents a follow-up study to our previous investigation of star formation in the cluster centre, extending our analysis out to a projected cluster radius of 1.5Mpc. Using the Near InfraRed Imager and Spectrograph on Gemini North Telescope we obtained deep H narrow-band imaging corresponding to the rest-frame wavelength of H{alpha} at the cluster's redshift. We identify a total of 163 potential cluster members in both pointings, excluding stars based on their near-infrared colours derived from VLT/HAWK-I imaging. Of these 163 objects 14 are spectroscopically confirmed cluster members, and 20 per cent are excess line emitters. We find no evidence of star formation activity within a radius of 200 kpc of the brightest cluster galaxy in the cluster core. Dust-corrected star formation rates (SFRs) of excess emitters outside this cluster quenching radius, R_Q_~200kpc, are on average <SFR>=2.7+/-1.0M_{sun}_/yr, but do not show evidence of increasing SFRs towards the extreme 1.5Mpc radius of the cluster. No individual cluster galaxy exceeds an SFR of 6M_{sun}_/yr. Massive galaxies (logM*/M_{sun}_>10.75) all have low specific SFRs (SSFRs, i.e. SFR per unit stellar mass). At fixed stellar mass, galaxies in the cluster centre have lower SSFRs than the rest of the cluster galaxies, which in turn have lower SSFRs than field galaxies at the same redshift by a factor of a few to 10. For the first time we can demonstrate through measurements of individual SFRs that already at very early epochs (at an age of the Universe of ~4.5Gyr) the suppression of star formation is an effect of the cluster environment which persists at fixed galaxy stellar mass.
- ID:
- ivo://CDS.VizieR/J/ApJ/707/1417
- Title:
- HST view of YSOs in the LMC
- Short Name:
- J/ApJ/707/1417
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used archival Hubble Space Telecope (HST) H{alpha} images to study the immediate environments of massive and intermediate-mass young stellar object (YSO) candidates in the Large Magellanic Cloud (LMC). The sample of YSO candidates, taken from Gruendl & Chu (2009, Cat. J/ApJS/184/172), was selected based on Spitzer IRAC and MIPS observations of the entire LMC and complementary ground-based optical and near-infrared observations. We found HST H{alpha} images for 99 YSO candidates in the LMC, of which 82 appear to be genuine YSOs. More than 95% of the YSOs are found to be associated with molecular clouds. YSOs are seen in three different kinds of environments in the H{alpha} images: in dark clouds, inside or on the tip of bright-rimmed dust pillars, and in small HII regions. Comparisons of spectral energy distributions for YSOs in these three different kinds of environments suggest that YSOs in dark clouds are the youngest, YSOs with small HII regions are the most evolved, and YSOs in bright-rimmed dust pillars span a range of intermediate evolutionary stages. This rough evolutionary sequence is substantiated by the presence of silicate absorption features in the Spitzer Infrared Spectrograph spectra of some YSOs in dark clouds and in bright-rimmed dust pillars, but not those of YSOs in small HII regions. We present a discussion on triggered star formation for YSOs in bright-rimmed dust pillars or in dark clouds adjacent to HII regions. As many as 50% of the YSOs are resolved into multiple sources in high-resolution HST images.
- ID:
- ivo://CDS.VizieR/V/165
- Title:
- IGAPS. merged IPHAS and UVEX of northern Galactic plane
- Short Name:
- V/165
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The INT Galactic Plane Survey (IGAPS) is the merger of the optical photometric surveys, IPHAS and UVEX, based on data from the Isaac Newton Telescope (INT) obtained between 2003 and 2018. Here, we present the IGAPS point source catalogue. It contains 295.4 million rows providing photometry in the filters, i, r, narrow-band H{alpha}, g, and URGO. The IGAPS footprint fills the Galactic coordinate range, |b|<5{deg} and 30{deg}<l<215{deg}. A uniform calibration, referred to as the Pan-STARRS system, is applied to g, r, and i, while the H{alpha} calibration is linked to r and then is reconciled via field overlaps. The astrometry in all five bands has been recalculated in the reference frame of Gaia Data Release 2. Down to i~20mag (Vega system), most stars are also detected in g, r, and H{alpha}. As exposures in the r band were obtained in both the IPHAS and UVEX surveys, typically a few years apart, the catalogue includes two distinct r measures, r_I_ and r_U_. The r 10{sigma} limiting magnitude is approximately 21, with median seeing of 1.1arcsec. Between approximately 13^th^ and 19^th^ mag in all bands, the photometry is internally reproducible to within 0.02 magnitudes. Stars brighter than r=19.5mag are tested for narrow-band H{alpha} excess signalling line emission, and for variation exceeding |r_I_-r_U_|=0.2mag. We find and flag 8292 candidate emission line stars and over 53000 variables (both at >5{sigma} confidence).
- ID:
- ivo://CDS.VizieR/J/MNRAS/407/2475
- Title:
- Ionized gas in E/S0 galaxies with dust lanes
- Short Name:
- J/MNRAS/407/2475
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of multicolour observations of 30 E/S0 galaxies with dust lanes. For each galaxy we obtained broad-band images and narrow-band images using interference filters isolating the H{alpha}+[NII] emission lines to derive the amount and morphology of dust and ionized gas. To improve the wavelength coverage we retrieved data from the Sloan Digital Sky Survey and Two Micron All Sky Survey and combined these with our data. Ionized gas is detected in 25 galaxies and shows in most cases a smooth morphology, although knots and filamentary structure are also observed in some objects.
- ID:
- ivo://CDS.VizieR/II/321
- Title:
- IPHAS DR2 Source Catalogue
- Short Name:
- II/321
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The INT/WFC Photometric H-Alpha Survey of the Northern Galactic Plane (IPHAS) is a 1860 deg^2^ imaging survey of the Northern Milky Way at red visible wavelengths. It covers Galactic latitudes |b|<5{deg} and longitudes l=30 to 215{deg} in the broad-band r, i and narrow-band H-alpha filters using the Wide Field Camera (WFC) on the 2.5-m Isaac Newton Telescope (INT) in La Palma. IPHAS Data Release 2 (DR2) is the first quality-controlled and globally calibrated source catalogue derived from the survey, providing single-epoch photometry for 219 million unique sources across 92% of the footprint. The observations were carried out between 2003 and 2012 at a median seeing of 1.1 arcsec (sampled at 0.33 arcsec/pixel) and to a mean 5-sigma depth of 21.2 (r), 20.0 (i) and 20.3 (H-alpha). The photometric calibration is in the Vega magnitude system and carries an external precision of 0.03mag (root-mean-square error). The catalogue includes all the sources which have been detected at a signal-to-noise ratio of 5 or better in at least one band. Many applications will require a combination of quality criteria to be applied to avoid faint stars or confused sources. The choice of quality criteria tensions completeness against reliability, and hence depends on the requirements of a project. To aid users, the data release paper (arXiv:1406.4862) recommends two sets of quality criteria, named "a10" and "a10point", which should satisfy most projects. As a minimum, the "a10" criteria select objects which have been detected at the minimum level of 10-sigma in all bands, without being saturated. Additional constraints are provided by the "a10point" criteria, which require objects to be point sources free of blending, unaffected by nearby bright stars, as well as being unsaturated >10-sigma detections in all bands. Sources in both categories are flagged in the catalogue using the boolean columns a10 and a10point. Imaging and auxiliary data are available from the project website (www.iphas.org).
- ID:
- ivo://CDS.VizieR/J/MNRAS/415/103
- Title:
- IPHAS T Tauri candidates in IC 1396
- Short Name:
- J/MNRAS/415/103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Isaac Newton Telescope (INT) Photometric H-Alpha Survey (IPHAS) is a 1800deg^2^ survey of the Northern Galactic Plane, reaching down to r'~21. We demonstrate how the survey can be used to (1) reliably select classical T Tauri star candidates and (2) constrain the mass accretion rates with an estimated relative uncertainty of 0.6dex. IPHAS is a necessary addition to spectroscopic surveys because it allows large and uniform samples of accretion rates to be obtained with a precise handle on the selection effects. We apply the method on a region of 7deg^2^ towards the HII region IC 1396 in Cepheus OB2 and identify 158 pre-main-sequence candidates with masses between 0.2 and 2.0M_{sun}_ and accretion rates between 10-9.2 and 10-7.0M_{sun}_/yr.
- ID:
- ivo://CDS.VizieR/J/ApJ/834/101
- Title:
- Keck/MOSFIRE spectroscopy of ZFOURGE galaxies
- Short Name:
- J/ApJ/834/101
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We compare galaxy scaling relations as a function of environment at z~2 with our ZFIRE survey where we have measured H{alpha} fluxes for 90 star-forming galaxies selected from a mass-limited (log(M_*_/M_{sun}_)>9) sample based on ZFOURGE. The cluster galaxies (37) are part of a confirmed system at z=2.095 and the field galaxies (53) are at 1.9<z<2.4; all are in the COSMOS legacy field. There is no statistical difference between H{alpha}-emitting cluster and field populations when comparing their star formation rate (SFR), stellar mass (M_*_), galaxy size (r_eff_), SFR surface density ({Sigma}(H{alpha}_star_)), and stellar age distributions. The only difference is that at fixed stellar mass, the H{alpha}-emitting cluster galaxies are log(r_eff_)~0.1 larger than in the field. Approximately 19% of the H{alpha} emitters in the cluster and 26% in the field are IR-luminous (L_IR_>2x10^11^L_{sun}_). Because the luminous IR galaxies in our combined sample are ~5 times more massive than the low-IR galaxies, their radii are ~70% larger. To track stellar growth, we separate galaxies into those that lie above, on, or below the H{alpha} star-forming main sequence (SFMS) using {Delta}SFR(M*)=+/-0.2dex. Galaxies above the SFMS (starbursts) tend to have higher H{alpha} SFR surface densities and younger light-weighted stellar ages than galaxies below the SFMS. Our results indicate that starbursts (+SFMS) in the cluster and field at z~2 are growing their stellar cores. Lastly, we compare to the (SFR-M*) relation from Rhapsody-G cluster simulations and find that the predicted slope is nominally consistent with the observations. However, the predicted cluster SFRs tend to be too low by a factor of ~2, which seems to be a common problem for simulations across environment.
- ID:
- ivo://CDS.VizieR/J/AJ/130/2571
- Title:
- KISS H{alpha}-selected survey list 3
- Short Name:
- J/AJ/130/2571
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The KPNO International Spectroscopic Survey (KISS) is an objective-prism survey designed to detect extragalactic emission-line objects. It combines many of the features of previous slitless spectroscopic surveys with the advantages of modern CCD detectors and is the first purely digital objective-prism survey for emission-line galaxies (ELGs). Here we present the third list of ELG candidates selected from our red spectral data, which cover the wavelength range 6400-7200{AA}. In most cases, the detected emission line is H{alpha}. The current survey list covers the region of the NOAO Deep Wide Field Survey (NDWFS). This survey covers two fields; the first is 3{deg}x3{deg} and located at RA=14h30m, DE=34{deg}30' (B1950.0), and the second is 2.3{deg}x4.0{deg} and centered at RA=2h7m30s, DE=-4{deg}44'. A total area of 19.65deg^2^ is covered by the KISS data. A total of 261 candidate emission-line objects have been selected for inclusion in the survey list (13.3deg^-2^). We tabulate accurate coordinates and photometry for each source, as well as estimates of the redshift, emission-line flux, and line equivalent width based on measurements of the digital objective-prism spectra. The properties of the KISS ELGs are examined using the available observational data.
