- ID:
- ivo://CDS.VizieR/J/MNRAS/405/783
- Title:
- Passive red spirals in Galaxy Zoo
- Short Name:
- J/MNRAS/405/783
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the spectroscopic properties and environments of red (or passive) spiral galaxies found by the Galaxy Zoo project. By carefully selecting face-on disc-dominated spirals, we construct a sample of truly passive discs (i.e. they are not dust reddened spirals, nor are they dominated by old stellar populations in a bulge). As such, our red spirals represent an interesting set of possible transition objects between normal blue spiral galaxies and red early types, making up ~6 per cent of late-type spirals. We use optical images and spectra from Sloan Digital Sky Survey to investigate the physical processes which could have turned these objects red without disturbing their morphology.
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- ID:
- ivo://CDS.VizieR/J/AJ/135/1624
- Title:
- PEARS emission-line galaxies
- Short Name:
- J/AJ/135/1624
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Hubble Space Telescope Advanced Camera for Surveys grism Probing Evolution And Reionization Spectroscopically (PEARS) survey provides a large dataset of low-resolution spectra from thousands of galaxies in the GOODS north and south fields. One important subset of objects in these data is emission-line galaxies (ELGs), and we have investigated several different methods aimed at systematically selecting these galaxies. Here, we present a new methodology and results of a search for these ELGs in the PEARS observations of the Hubble Ultra Deep Field (HUDF) using a 2D detection method that utilizes the observation that many emission lines originate from clumpy knots within galaxies. This 2D line-finding method proves to be useful in detecting emission lines from compact knots within galaxies that might not otherwise be detected using more traditional 1D line-finding techniques.
- ID:
- ivo://CDS.VizieR/J/AJ/141/64
- Title:
- PEARS emission-line galaxies spectroscopy
- Short Name:
- J/AJ/141/64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present spectroscopy of 76 emission-line galaxies (ELGs) in Chandra Deep Field South taken with the LDSS3 spectrograph on the Magellan Telescope. These galaxies are selected because they have emission lines with the Advanced Camera for Surveys (ACS) grism data in the Hubble Space Telescope Probing Evolution and Reionization Spectroscopically (PEARS) grism Survey. The ACS grism spectra cover the wavelength range 6000-9700{AA} and most PEARS grism redshifts are based on a single emission line + photometric redshifts from broadband colors; the Magellan spectra cover a wavelength range from 4000{AA} to 9000{AA} and provide a check on redshifts derived from PEARS data.
414. PESSTO catalog
- ID:
- ivo://CDS.VizieR/J/A+A/579/A40
- Title:
- PESSTO catalog
- Short Name:
- J/A+A/579/A40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Public European Southern Observatory Spectroscopic Survey of Transient Objects (PESSTO) began as a public spectroscopic survey in April 2012. PESSTO classifies transients from publicly available sources and wide-field surveys, and selects science targets for detailed spectroscopic and photometric follow-up. PESSTO runs for nine months of the year, January - April and August - December inclusive, and typically has allocations of 10 nights per month. We describe the data reduction strategy and data products that are publicly available through the ESO archive as the Spectroscopic Survey data release 1 (SSDR1). PESSTO uses the New Technology Telescope with the instruments EFOSC2 and SOFI to provide optical and NIR spectroscopy and imaging. We target supernovae and optical transients brighter than 20.5^m^ for classification. Science targets are selected for follow-up based on the PESSTO science goal of extending knowledge of the extremes of the supernova population. We use standard EFOSC2 set-ups providing spectra with resolutions of 13-18{AA} between 3345-9995{AA}. A subset of the brighter science targets are selected for SOFI spectroscopy with the blue and red grisms (0.935-2.53{mu}m and resolutions 23-33{AA}) and imaging with broadband JHK_s_ filters. This first data release (SSDR1) contains flux calibrated spectra from the first year (April 2012-2013). A total of 221 confirmed supernovae were classified, and we released calibrated optical spectra and classifications publicly within 24h of the data being taken (via WISeREP). The data in SSDR1 replace those released spectra. They have more reliable and quantifiable flux calibrations, correction for telluric absorption, and are made available in standard ESO Phase 3 formats. We estimate the absolute accuracy of the flux calibrations for EFOSC2 across the whole survey in SSDR1 to be typically ~15%, although a number of spectra will have less reliable absolute flux calibration because of weather and slit losses. Acquisition images for each spectrum are available which, in principle, can allow the user to refine the absolute flux calibration. The standard NIR reduction process does not produce high accuracy absolute spectrophotometry but synthetic photometry with accompanying JHK_s_ imaging can improve this. Whenever possible, reduced SOFI images are provided to allow this. Future data releases will focus on improving the automated flux calibration of the data products. The rapid turnaround between discovery and classification and access to reliable pipeline processed data products has allowed early science papers in the first few months of the survey.
- ID:
- ivo://CDS.VizieR/J/A+A/506/999
- Title:
- Photometric Calibration of SNLS
- Short Name:
- J/A+A/506/999
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the photometric calibration of the SuperNova Legacy Survey (SNLS) three year dataset. The SNLS corresponds to the DEEP component of the larger Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). The SNLS repeatedly monitors four one square degree fields (labeled D[1-4]) with the MegaCam wide-field imager, in the g, r, i and z bands. u-band observations of the same fields are also available, although not formally part of the SNLS dataset. The non-uniformities of the MegaCam imager photometric response have been mapped as a function of the position on the focal plane. The fluxes, measured on the survey images processed with the CFHT Elixir pipeline, have been corrected for these non-uniformities in order to obtain measurements that are uniform at the ~1% level. The MegaCam passband transmissions were found to be non-uniform, the filters being 3 to 6 nanometers bluer on the edges of the camera than on the center. This result agrees with the filter scans provided by the filter manufacturer (Sagem/REOSC). This has important consequences on the definition of the MegaCam magnitudes: the natural magnitude system depends on the focal plane location where the observations were made. In order not to break the connection between calibrated magnitudes and their physical flux counterparts, we chose to report the *natural magnitudes* of each object, measured in the MegaCam passbands, at the focal plane location where the object was observed. We call this system, "Local Natural Magnitudes". The non-uniformities of the MegaCam effective passbands are small and, for main sequence stellar objects, they may be accounted for using linear color corrections. The relation between the Local Natural Magnitudes of a given star, observed at two locations x_0 and x of the focal plane are: g|x = g|x_0 + dk_g_gr(x) * ( (g-r)|x_0 - (g-r)BD+17|x_0 ) ... z|x = z|x_0 + dk_z_iz(x) * ( (i-z)|x_0 - (i-z)BD+17|x_0 ) where the dk(x) are (position dependant) color terms. We provide dk(x) maps for each MegaCam band (see below). The SNLS 3 year calibration relies on the (Landolt, 1992AJ....104..340) standard star catalog. Landolt fields are observed during each photometric night along with the SNLS fields. Zero-points are derived from these observations. Stable and isolated stars are detected on the SNLS fields and selected as "tertiary standards". The calibrated magnitudes of each tertiary standard obtained under photometric conditions are combined to produce a calibration catalog for each SNLS field. To interpret the tertiary standard magnitudes as physical fluxes, we need a primary standard, i.e. a star with known MegaCam magnitudes and whose spectral energy distribution has been measured absolutely. The SNLS uses BD+17 4708 whose SED has been measured in Bohlin & Gilliland, 2004, Cat. <J/AJ/128/3053> using the HST STIS and NICMOS spectrographs. BD+17 4708 has not been directly observed by SNLS, however, its MegaCam magnitudes were inferred from its known Landolt magnitudes (this paper, table 7). The tertiary star Local Natural Magnitudes are defined so that the associated physical broadband flux f|x is given by: f|x = 10^{-0.4*(m|x-m_ref_)}^*{int}[S_ref(l)_*T(l;x)]dl where m|x is the tertiary star magnitudes at location x on the focal plane, m_ref_ is the MegaCam magnitude of BD+17 4708 (at the center of the focal plane, see table 7 of this paper), S_ref(l)_ is the SED of BD+17 4708 measured in 2004AJ....128.3053B, and T(l;x) is the effective passband of MegaCam at location x. Attached is all the necessary information to tie MegaCam observations to this system. We provide (a) the griz magnitudes of the SNLS tertiary standards for all four SNLS fields (b) the MegaCam open transmission and the ugriz MegaCam filter scans at various position along a diagonal (c) the final uncertainty budget in the form of 3 covariance matrices. The u-band observations of the SNLS DEEP fields are not formally part of the SNLS. Nevetheless we give u-band magnitudes for a subset of the SNLS tertiary stars.
- ID:
- ivo://CDS.VizieR/J/MNRAS/477/845
- Title:
- Photometric catalogue of CALIFA galaxies
- Short Name:
- J/MNRAS/477/845
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an extensive compendium of photometrically determined structural properties for all Calar Alto Legacy Integral Field spectroscopy Area (CALIFA)galaxies in the third data release (DR3). We exploit Sloan Digital Sky Survey (SDSS) images in order to extract one-dimensional (1D) gri surface brightness profiles for all CALIFA DR3 galaxies. We also derive a variety of non-parametric quantities and parametric models fitted to 1D i-band profiles. The galaxy images are decomposed using the 2D bulge-disc decomposition programs IMFIT and GALFIT. The relative performance and merit of our 1D and 2D modelling approaches are assessed. Where possible, we compare and augment our photometry with existing measurements from the literature. Close agreement is generally found with the studies of Walcher et al. (2014A&A...569A...1W) and Mendez-Abreu et al. (2017A&A...598A..32M, Cat. J/A+A/598/A32), though some significant differences exist. Various structural metrics are also highlighted on account of their tight dispersion against an independent variable, such as the circular velocity.
- ID:
- ivo://CDS.VizieR/J/MNRAS/419/80
- Title:
- Photometric Classification Catalogue of SDSS DR7
- Short Name:
- J/MNRAS/419/80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of about six million unresolved photometric detections in the Sloan Digital Sky Survey (SDSS) Seventh Data Release, classifying them into stars, galaxies and quasars. We use a machine learning classifier trained on a subset of spectroscopically confirmed objects from 14th to 22nd magnitude in the SDSS i band. Our catalogue consists of 2430625 quasars, 3544036 stars and 63586 unresolved galaxies from 14th to 24th magnitude in the SDSS i-band. Our algorithm recovers 99.96 per cent of spectroscopically confirmed quasars and 99.51 per cent of stars to i~21.3 in the colour window that we study. The level of contamination due to data artefacts for objects beyond i=21.3 is highly uncertain and all mention of completeness and contamination in the paper are valid only for objects brighter than this magnitude. However, a comparison of the predicted number of quasars with the theoretical number counts shows reasonable agreement.
- ID:
- ivo://CDS.VizieR/J/A+A/584/A44
- Title:
- Photometric classification of QSO from RCS-2
- Short Name:
- J/A+A/584/A44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new quasar candidate catalogs from the Red-Sequence Cluster Survey 2 (RCS-2), identified solely from photometric information using a Random Forest algorithm. The algorithm is trained using a well-defined SDSS spectroscopic sample of quasars and stars. The algorithm identifies putative quasars from broadband magnitudes (g, r, i, z) and colors. Exploiting NUV GALEX measurements for a subset of the objects, we refine the classifier by adding new information. An additional subset of the data with WISE W1 and W2 bands is also studied. Upon analyzing 542,897 RCS-2 point sources, the algorithm identified 21,501 quasar candidates, with a training-set-derived precision of 89.5% and recall of 88.4%. These performance metrics improve for the GALEX subset; 6530 quasar candidates are identified from 16898 sources, with a precision and recall respectively of 97.0% and 97.5%. Algorithm performance is further improved when WISE data are included, with precision and recall increasing to 99.3% and 99.1% respectively for 21834 quasar candidates from 242902 sources. After merging these samples and removing duplicates, we obtain 38257 candidates.
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/3649
- Title:
- Photometric data for ASASSN-15ed
- Short Name:
- J/MNRAS/453/3649
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of the spectroscopic and photometric monitoring campaign of ASASSN-15ed. The transient was discovered quite young by the All Sky Automated Survey for SuperNovae (ASAS-SN) survey. Amateur astronomers allowed us to sample the photometric SN evolution around maximum light, which we estimate to have occurred on JD=2457087.4+/-0.6 in the r band. Its apparent r-band magnitude at maximum was r=16.91+/-0.10, providing an absolute magnitude M_r_~-20.04+/-0.20, which is slightly more luminous than the typical magnitudes estimated for Type Ibn SNe. The post-peak evolution was well monitored, and the decline rate (being in most bands around 0.1 mag/d during the first 25 d after maximum) is marginally slower than the average decline rates of SNe Ibn during the same time interval. The object was initially classified as a Type Ibn SN because early-time spectra were characterized by a blue continuum with superimposed narrow P-Cygni lines of HeI, suggesting the presence of a slowly moving (1200-1500 km/s), He-rich circumstellar medium. Later on, broad P-Cygni HeI lines became prominent. The inferred velocities, as measured from the minimum of the broad absorption components, were between 6000 and 7000 km/s. As we attribute these broad features to the SN ejecta, this is the first time we have observed the transition of a Type Ibn SN to a Type Ib SN.
- ID:
- ivo://CDS.VizieR/J/ApJ/787/163
- Title:
- Photometric data for SN 2009ip
- Short Name:
- J/ApJ/787/163
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present time series photometric and spectroscopic data for the transient SN 2009ip from the start of its outburst in 2012 September until 2013 November. These data were collected primarily with the new robotic capabilities of the Las Cumbres Observatory Global Telescope Network, a specialized facility for time domain astrophysics, and includes supporting high-resolution spectroscopy from the Southern Astrophysical Research Telescope, Kitt Peak National Observatory, and Gemini Observatory. Based on our nightly photometric monitoring, we interpret the strength and timing of fluctuations in the light curve as interactions between fast-moving ejecta and an inhomogeneous circumstellar material (CSM) produced by past eruptions of this massive luminous blue variable (LBV) star. Our time series of spectroscopy in 2012 reveals that, as the continuum and narrow H{alpha} flux from CSM interactions declines, the broad component of H{alpha} persists with supernova (SN)-like velocities that are not typically seen in LBVs or SN impostor events. At late times, we find that SN 2009ip continues to decline slowly, at <~0.01 mag/day, with small fluctuations in slope similar to Type IIn supernovae (SNe IIn) or SN impostors but no further LBV-like activity. The late-time spectrum features broad calcium lines similar to both late-time SNe and SN impostors. In general, we find that the photometric and spectroscopic evolution of SN 2009ip is more similar to SNe IIn than either continued eruptions of an LBV star or SN impostors but we cannot rule out a nonterminal explosion. In this context, we discuss the implications for episodic mass loss during the late stages of massive star evolution.
