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2971. IPHAS T Tauri candidates in IC 1396
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.
2972. I photometry of Cl 0024+16
ID:
ivo://CDS.VizieR/J/ApJ/591/53
Title:
I photometry of Cl 0024+16
Short Name:
J/ApJ/591/53
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe a new wide-field Hubble Space Telescope survey of the galaxy cluster Cl 0024+16 (z~0.4) consisting of a sparsely sampled mosaic of 39 Wide Field Planetary Camera 2 images that extends to a cluster radius of ~5Mpc. Together with extensive ground-based spectroscopy taken from the literature, augmented with over a hundred newly determined redshifts, this unique data set enables us to examine environmental influences on the properties of cluster members from the inner core to well beyond the virial radius (~1.7Mpc). We catalog photometric measures for 22000 objects to I>~25 and assign morphological types for 2181 to I=22.5, of which 195 are spectroscopically confirmed cluster members.
2973. I photometry of early-type galaxies
ID:
ivo://CDS.VizieR/J/AJ/116/2728
Title:
I photometry of early-type galaxies
Short Name:
J/AJ/116/2728
Date:
21 Oct 2021
Publisher:
CDS
Description:
As part of a project to compare the fundamental plane and Tully-Fisher distance scales, we present here I-band CCD photometry for 636 early-type galaxies in eight clusters and groups of galaxies. These are the A262, A1367, Coma (A1656), A2634, Cancer and Pegasus Clusters, and the NGC 383 and NGC 507 Groups. Sample selection, cluster properties, and cluster membership assignment criteria are discussed. We present photometric parameters that are used in the fundamental plane relation, the effective radius r_e_, and the effective surface brightness {mu}_e_, as derived from a r^1/4^ fit to the observed radial photometric profile of each galaxy. A comparison with similar data found in the literature for the Coma Cluster shows that large systematic uncertainties can be introduced in the measurement of r_e_ and {mu}_e_ by the particular method used to derive those parameters. However, the particular combination of these two parameters that enters in the fundamental plane relation is a quantity that can be measured with high accuracy.
2974. iPTF 16asu photometry follow-up
ID:
ivo://CDS.VizieR/J/ApJ/851/107
Title:
iPTF 16asu photometry follow-up
Short Name:
J/ApJ/851/107
Date:
21 Oct 2021
Publisher:
CDS
Description:
Wide-field surveys are discovering a growing number of rare transients whose physical origin is not yet well understood. Here we present optical and UV data and analysis of intermediate Palomar Transient Factory (iPTF) 16asu, a luminous, rapidly evolving, high-velocity, stripped-envelope supernova (SN). With a rest-frame rise time of just four days and a peak absolute magnitude of M_g_=-20.4mag, the light curve of iPTF 16asu is faster and more luminous than that of previous rapid transients. The spectra of iPTF 16asu show a featureless blue continuum near peak that develops into an SN Ic-BL spectrum on the decline. We show that while the late-time light curve could plausibly be powered by 56Ni decay, the early emission requires a different energy source. Nondetections in the X-ray and radio strongly constrain the energy coupled to relativistic ejecta to be at most comparable to the class of low-luminosity gamma-ray bursts (GRBs). We suggest that the early emission may have been powered by either a rapidly spinning-down magnetar or by shock breakout in an extended envelope of a very energetic explosion. In either scenario a central engine is required, making iPTF 16asu an intriguing transition object between superluminous SNe, SNe Ic-BL, and low-luminosity GRBs.
2975. iPTF 14gqr (SN 2014ft) photometry
ID:
ivo://CDS.VizieR/J/other/Sci/362.201
Title:
iPTF 14gqr (SN 2014ft) photometry
Short Name:
J/other/Sci/362.
Date:
21 Oct 2021
Publisher:
CDS
Description:
Compact neutron star binary systems are produced from binary massive stars through stellar evolution involving up to two supernova explosions. The final stages in the formation of these systems have not been directly observed. We report the discovery of iPTF 14gqr (SN 2014ft), a type Ic supernova with a fast-evolving light curve indicating an extremely low ejecta mass (~=0.2 solar masses) and low kinetic energy (~=2x10^50^ergs). Early photometry and spectroscopy reveal evidence of shock cooling of an extended helium-rich envelope, likely ejected in an intense pre-explosion mass-loss episode of the progenitor. Taken together, we interpret iPTF 14gqr as evidence for ultra-stripped supernovae that form neutron stars in compact binary systems.
2976. IRAC and JHKs photometry of h and chi Persei
ID:
ivo://CDS.VizieR/J/ApJ/659/599
Title:
IRAC and JHKs photometry of h and chi Persei
Short Name:
J/ApJ/659/599
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe IRAC 3.6-8um observations and ground-based near-IR JHKs photometry from Mimir and 2MASS of the massive double cluster h and chi Persei complete to J=15.5 (M~1.3M_{sun}_). Within 25' of the cluster centers we detect ~11000 sources with J<=15.5, ~7000 sources with [4.5]<=15, and ~5000 sources with [8]<=14.5. In both clusters the surface density profiles derived from the 2MASS data decline with distance from the cluster centers as expected for a bound cluster. Within 15' of the cluster centers, ~50% of the stars lie on a reddened ~13Myr isochrone; at 15'-25' from the cluster centers, ~40% lie on this isochrone. Thus, the optical/2MASS color-magnitude diagrams indicate that h and chi Per are accompanied by a halo population with roughly the same age and distance as the two dense clusters.
2977. IRAC counterparts of 6cm galaxies in EGS
ID:
ivo://CDS.VizieR/J/AJ/132/2159
Title:
IRAC counterparts of 6cm galaxies in EGS
Short Name:
J/AJ/132/2159
Date:
21 Oct 2021
Publisher:
CDS
Description:
A new 6cm survey of almost 0.6deg^2^ to a limit of 0.55mJy/beam (10sigma) finds 37 isolated radio sources and seven radio-source pairs (not necessarily physical companions). Infrared Array Camera (IRAC) counterparts are identified for at least 92% of the radio sources within the area of deep IRAC coverage, which includes 31 isolated sources and six pairs. This contrasts with an identification rate of <74% to R<23.95 in visible light. Eight of the IRAC galaxies have power-law spectral energy distributions, implying that the mid-infrared emission comes from a powerful active galactic nucleus (AGN). The remaining 26 IRAC galaxies show stellar emission in the mid-infrared, probably in most of these galaxies because the stellar emission is bright enough to outshine an underlying AGN.
2978. IRAC Dark Field, ELAIS-N1 and ADF-S galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/472/4259
Title:
IRAC Dark Field, ELAIS-N1 and ADF-S galaxies
Short Name:
J/MNRAS/472/4259
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first detailed analysis of three extragalactic fields (IRAC Dark Field, ELAIS-N1, ADF-S) observed by the infrared satellite, AKARI, using an optimised data analysis toolkit specifically for the processing of extragalactic point sources. The InfaRed Camera (IRC) on AKARI complements the Spitzer space telescope via its comprehensive coverage between 8-24{mu}m filling the gap between the Spitzer IRAC and MIPS instruments.
2979. IRAC fluxes of the ID8 and P1121 systems
ID:
ivo://CDS.VizieR/J/AJ/157/202
Title:
IRAC fluxes of the ID8 and P1121 systems
Short Name:
J/AJ/157/202
Date:
21 Oct 2021
Publisher:
CDS
Description:
The most dramatic phases of terrestrial planet formation are thought to be oligarchic and chaotic growth, on timescales of up to 100-200 Myr, when violent impacts occur between large planetesimals of sizes up to protoplanets. Such events are marked by the production of large amounts of debris, as has been observed in some exceptionally bright and young debris disks (termed extreme debris disks). Here we report five years of Spitzer measurements of such systems around two young solar-type stars: ID8 and P1121. The short-term (weekly to monthly) and long-term (yearly) disk variability is consistent with the aftermaths of large impacts involving large asteroid-sized bodies. We demonstrate that an impact-produced clump of optically thick dust, under the influence of the dynamical and viewing geometry effects, can produce short-term modulation in the disk light curves. The long-term disk flux variation is related to the collisional evolution within the impact-produced fragments once released into a circumstellar orbit. The time-variable behavior observed in the P1121 system is consistent with a hypervelocity impact prior to 2012 that produced vapor condensates as the dominant impact product. Two distinct short-term modulations in the ID8 system suggest two violent impacts at different times and locations. Its long-term variation is consistent with the collisional evolution of two different populations of impact-produced debris dominated by either vapor condensates or escaping boulders. The bright, variable emission from the dust produced in large impacts from extreme debris disks provides a unique opportunity to study violent events during the era of terrestrial planet formation.
2980. IRAC HUDF and GOODS ultradeep surveys
ID:
ivo://CDS.VizieR/J/ApJS/221/23
Title:
IRAC HUDF and GOODS ultradeep surveys
Short Name:
J/ApJS/221/23
Date:
21 Oct 2021
Publisher:
CDS
Description:
The IRAC ultradeep field and IRAC Legacy over GOODS programs are two ultradeep imaging surveys at 3.6 and 4.5{mu}m with the Spitzer Infrared Array Camera (IRAC). The primary aim is to directly detect the infrared light of reionization epoch galaxies at z>7 and to constrain their stellar populations. The observations cover the Hubble Ultra Deep Field (HUDF), including the two HUDF parallel fields, and the CANDELS/GOODS-South, and are combined with archival data from all previous deep programs into one ultradeep data set. The resulting imaging reaches unprecedented coverage in IRAC 3.6 and 4.5{mu}m ranging from >50hr over 150arcmin^2^, >100hr over 60sq arcmin^2^, to ~200hr over 5-10arcmin^2^. This paper presents the survey description, data reduction, and public release of reduced mosaics on the same astrometric system as the CANDELS/GOODS-South Wide Field Camera 3 (WFC3) data. To facilitate prior-based WFC3+IRAC photometry, we introduce a new method to create high signal-to-noise PSFs from the IRAC data and reconstruct the complex spatial variation due to survey geometry. The PSF maps are included in the release, as are registered maps of subsets of the data to enable reliability and variability studies. Simulations show that the noise in the ultradeep IRAC images decreases approximately as the square root of integration time over the range 20-200hr, well below the classical confusion limit, reaching 1{sigma} point-source sensitivities as faint as 15nJy (28.5 AB) at 3.6{mu}m and 18nJy (28.3 AB) at 4.5{mu}m. The value of such ultradeep IRAC data is illustrated by direct detections of z=7-8 galaxies as faint as H_AB_=28.