- ID:
- ivo://CDS.VizieR/J/ApJ/882/120
- Title:
- CfA, CSP, BSP and LOSS spec. & phot. of SNe Ia
- Short Name:
- J/ApJ/882/120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- SNe Ia play key roles in revealing the accelerating expansion of the universe, but our knowledge of their progenitors is still very limited. Here we report the discovery of a rigid dichotomy in circumstellar (CS) environments around two subclasses of SNe Ia as defined by their distinct photospheric velocities. For the SNe Ia with high photospheric velocities (HVs), we found a significant excess flux in blue light 60-100 days past maximum, while this phenomenon is absent for SNe with normal photospheric velocity. This blue excess can be attributed to light echoes by circumstellar dust located at a distance of about (1-2)x10^17^cm from the HV subclass. Moreover, we also found that the HV SNe Ia show systematically evolving NaI absorption line by performing a systematic search of variable NaI absorption lines in spectra of all SNe Ia, whereas this evolution is rarely seen in normal ones. The evolving NaI absorption can be modeled in terms of photoionization model, with the location of the gas clouds at a distance of about 2x10^17^cm, in striking agreement with the location of CS dust inferred from B-band light-curve excess. These observations show clearly that the progenitors of HV subclass are likely from single-degenerate progenitor system (i.e., symbiotic binary), while the NV subclass may arise from double-degenerate system.
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- ID:
- ivo://CDS.VizieR/J/ApJS/220/9
- Title:
- CfAIR2: NIR light curves of Type Ia SNe
- Short Name:
- J/ApJS/220/9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- CfAIR2 is a large, homogeneously reduced set of near-infrared (NIR) light curves (LCs) for Type Ia supernovae (SNe Ia) obtained with the 1.3m Peters Automated InfraRed Imaging TELescope. This data set includes 4637 measurements of 94 SNe Ia and 4 additional SNe Iax observed from 2005 to 2011 at the Fred Lawrence Whipple Observatory on Mount Hopkins, Arizona. CfAIR2 includes JHKs photometric measurements for 88 normal and 6 spectroscopically peculiar SN Ia in the nearby universe, with a median redshift of z~0.021 for the normal SN Ia. CfAIR2 data span the range from -13 days to +127 days from B-band maximum. More than half of the LCs begin before the time of maximum, and the coverage typically contains ~13-18 epochs of observation, depending on the filter. We present extensive tests that verify the fidelity of the CfAIR2 data pipeline, including comparison to the excellent data of the Carnegie Supernova Project. CfAIR2 contributes to a firm local anchor for SN cosmology studies in the NIR. Because SN Ia are more nearly standard candles in the NIR and are less vulnerable to the vexing problems of extinction by dust, CfAIR2 will help the SN cosmology community develop more precise and accurate extragalactic distance probes to improve our knowledge of cosmological parameters, including dark energy and its potential time variation.
- ID:
- ivo://CDS.VizieR/J/ApJS/200/12
- Title:
- CfA4: light curves for 94 type Ia SNe
- Short Name:
- J/ApJS/200/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present multi-band optical photometry of 94 spectroscopically confirmed Type Ia supernovae (SNe Ia) in the redshift range 0.0055-0.073, obtained between 2006 and 2011. There are a total of 5522 light-curve points. We show that our natural-system SN photometry has a precision of <~0.03mag in BVr'i', <~0.06mag in u', and <~0.07mag in U for points brighter than 17.5mag and estimate that it has a systematic uncertainty of 0.014, 0.010, 0.012, 0.014, 0.046, and 0.073mag in BVr'i'u'U, respectively. Comparisons of our standard-system photometry with published SN Ia light curves and comparison stars reveal mean agreement across samples in the range of ~0.00-0.03mag. The current sample of low-z SNe Ia is now sufficiently large to remove most of the statistical sampling error from the dark-energy error budget.
- ID:
- ivo://nasa.heasarc/zcat
- Title:
- CfA Redshift Catalog (June 1995 Version)
- Short Name:
- CFAZ
- Date:
- 25 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The ZCAT database contains the CfA Redshift Catalog, which incorporates much of the latest velocity data from the Whipple Observatory and other sources, as well as velocities from earlier compilations such as the "Second Reference Catalog" of de Vaucouleurs, de Vaucouleurs, and Corwin; the "Index of Galaxy Spectra" of Gisler and Friel; and the "Catalog of Radial Velocities of Galaxies" of Palumbo, Tanzella-Nitti, and Vettolani. It includes BT magnitudes, some UGC numbers, and increased "accuracy" in the velocity source information. The data presented here have primarily been assembled for the purpose of studying the large scale structure of the universe, and, as such, are nearly complete in redshift information, but are not necessarily complete in such categories as diameter, magnitude, and cross-references to other catalogues. The original HEASARC version was constructed based on an earlier version of the catalog and was released on November 15, 1996. The HEASARC created the current version of ZCAT in February 2001 based on CDS/ADC Catalog VII/193, "The CfA Redshift Catalogue", Version June 1995, tables <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/193/zcat.dat">https://cdsarc.cds.unistra.fr/ftp/cats/VII/193/zcat.dat</a> and zbig.dat. The former table contains the main body of the CFA Redshift Catalog (57536 objects) and entries from it are distinguishable in the current database by having either listed radial velocity values but not redshifts or neither, while the latter table contains 1202 high-redshift galaxies (distinguishable in the current database by their having listed redshift values but not radial velocities). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cfa2s
- Title:
- CfA Redshift Survey: South Galactic Cap Data
- Short Name:
- CfARed.S.
- Date:
- 25 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Center for Astrophysics (CfA) Redshift Survey South Galactic Cap (CFA2S) Catalog contains redshifts for a sample of about 4300 galaxies with blue (Zwicky B(0) type) magnitude <= 15.5 covering the range from 20 h to 4h in right ascension and from -2.5 deg to 90 deg in declination. This sample is complete for all galaxies in the merge of the Zwicky et al. and Nilson catalogs in the south Galactic cap. Redshifts for 2964 of these were measured as part of the second CfA Redshift Survey. The data reveal large voids in the foreground and background of the Perseus-Pisces Supercluster. The largest of these voids lies at a mean velocity ~ 8000km/s, has diameter of ~ 5000km/s, and is enclosed by a complex of dense structures. The large structure known as the Perseus-Pisces Supercluster forms the near side of this complex. On the far side of this large void, at a mean velocity of ~ 12000km/s, there is another coherent dense wall. The structures in this survey support the view that galaxies generally lie on surfaces surrounding or nearly surrounding low-density regions or voids. This table was created by the HEASARC in March 2005 based on CDS table J/ApJS/121/287/cfa2s.dat.gz This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/J/AJ/104/1706
- Title:
- CFH Blue Grens Quasar Candidates
- Short Name:
- J/AJ/104/1706
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
3337. CF-HiZELS survey
- ID:
- ivo://CDS.VizieR/J/MNRAS/451/2303
- Title:
- CF-HiZELS survey
- Short Name:
- J/MNRAS/451/2303
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from the largest contiguous narrow-band survey in the near-infrared. We have used the wide-field infrared camera/Canada-France-Hawaii Telescope and the lowOH2 filter (1.187+/-0.005{mu}m) to survey ~10deg^2^ of contiguous extragalactic sky in the SA22 field. A total of ~6000 candidate emission-line galaxies are found. We use deep ugrizJK data to obtain robust photometric redshifts. We combine our data with the High-redshift(Z) Emission Line Survey (HiZELS), explore spectroscopic surveys (VVDS, VIPERS) and obtain our own spectroscopic follow-up with KMOS, FMOS and MOSFIRE to derive large samples of high-redshift emission-line selected galaxies: 3471 H{alpha} emitters at z=0.8, 1343 [OIII] + H{beta} emitters at z=1.4 and 572 [OII] emitters at z=2.2. We probe comoving volumes of >10^6^Mpc^3^ and find significant overdensities, including an 8.5{sigma} (spectroscopically confirmed) overdensity of H{alpha} emitters at z=0.81. We derive H{alpha}, [OIII] + H{beta} and [OII] luminosity functions at z=0.8, 1.4, 2.2, respectively, and present implications for future surveys such as Euclid. Our uniquely large volumes/areas allow us to subdivide the samples in thousands of randomized combinations of areas and provide a robust empirical measurement of sample/cosmic variance. We show that surveys for star-forming/emission-line galaxies at a depth similar to ours can only overcome cosmic-variance (errors <10 percent) if they are based on volumes >5x10^5^Mpc^3^; errors on L* and {phi}* due to sample (cosmic) variance on surveys probing ~10^4^ and ~10^5^Mpc^3^ are typically very high: ~300 and ~40-60 percent, respectively.
3338. CFHQSIR survey
- ID:
- ivo://CDS.VizieR/J/A+A/616/A55
- Title:
- CFHQSIR survey
- Short Name:
- J/A+A/616/A55
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) has been conducted over a five-year period at the CFHT with the MegaCam instrument, totaling 450 nights of observations. The Wide Synoptic Survey is one component of the CFHTLS, covering 155 square degrees in four patches of 23 to 65 square degrees through the whole MegaCam filter set (u*, g', r', i', z') down to i'_{AB} = 24.5. With the motivation of searching for high-redshift quasars at redshifts above 6.5, we extend the multi-wavelength CFHTLS-Wide data in the Y-band down to magnitudes of {sim} 22.5 for point sources (5{sigma}). We observed the four CFHTLS-Wide fields (except one quarter of the W3 field) in the Y-band with the WIRCam instrument (Wide-field InfraRed Camera) at the CFHT. Each field was visited twice, at least three weeks apart. Each visit consisted of two dithered exposures. The images are reduced with the Elixir software used for the CFHTLS and modified to account for the properties of near-InfraRed (IR) data. Two series of image stacks are subsequently produced: four-image stacks for each WIRCam pointing, and one-square- degree tiles matched to the format of the CFHTLS data release. Photometric calibration is performed on stars by fitting stellar spectra to their CFHTLS photometric data and extrapolating their Y-band magnitudes. After corrections accounting for correlated noise, we measure a limiting magnitude of Y_{AB}~=22.4 for point sources (5{sigma}) in an aperture diameter of 0.93 arcsecs, over 130 square degrees. We produce a multi-wavelength catalogue combining the CFHTLS-Wide optical data with our CFHQSIR (Canada-France High-z quasar survey in the near-InfraRed) Y-band data. We derive the Y-band number counts and compare them to the Vista Deep Extragalactic Observations survey (VIDEO). We find that the addition of the CFHQSIR Y-band data to the CFHTLS optical data increases the accuracy of photometric redshifts and reduces the outlier rate from 13.8% to 8.8% in the redshift range 1.05<~z<~1.2. The images and the catalogue for 8.6 million sources down to [(z'>=23.5) {lor} (Y>=23.0)] are released and available at the following URL: http://apps.canfar.net/storage/list/cjw/cfhqsir
- ID:
- ivo://CDS.VizieR/J/AJ/119/1268
- Title:
- CFHT adaptive optics observations of M15
- Short Name:
- J/AJ/119/1268
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used an Imaging Fabry-Perot Spectrophotometer with the Adaptive Optics Bonnette on the Canada-France-Hawaii Telescope to measure stellar radial velocities in the globular cluster M15 (NGC 7078). An average seeing of 0.15'' FWHM, with the best-seeing image having 0.09'', allowed us to measure accurately the velocities for five stars within 1'' of the center of M15. Our estimate of the second moment of the velocity distribution (i.e., the dispersion, ignoring rotation) inside a radius of 2'' is 11.5 km.s^-1^, the same value we find out to a radius of about 6''. However, the projected net rotation does increase dramatically at small radii, as our previous observations led us to suspect. The rotation amplitude inside a radius of 3.4'' is v=10.4+/-2.7 km.s^-1^ and the dispersion after removing the rotation is {sigma}=10.3+/-1.4 km.s^-1^, so v/{sigma} {~} 1 in this region. In addition, the position angle of the projected rotation axis differs by 100 degrees from that of the net cluster rotation at larger radii.
- ID:
- ivo://CDS.VizieR/J/A+A/646/A71
- Title:
- CFHTLenS galaxy bias and redshift distribution
- Short Name:
- J/A+A/646/A71
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Galaxy models predict a tight relation between the clustering of galaxies and dark matter on cosmological scales, but predictions differ notably in the details. We used this opportunity and tested two semi-analytic models by the Munich and Durham groups with data from the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS). For the test we measured the scale-dependent galaxy bias factor b(k) and correlation factor r(k) from linear to non-linear scales of k=~10h/Mpc at two redshifts z{bar}=0.35, 0.51 for galaxies with stellar mass between 5x10^9^ and 3x10^11^h_70_^-2^M_{sun|_. Our improved gravitational lensing technique accounts for the intrinsic alignment of sources and the magnification of lens galaxies for better constraints for the galaxy-matter correlation r(k). Galaxy bias in CFHTLenS increases with k and stellar mass; it is colour-dependent, revealing the individual footprints of galaxy types. Despite a reasonable model agreement for the relative change with both scale and galaxy properties, there is a clear conflict for b(k) with no model preference: the model galaxies are too weakly clustered. This may flag a model problem at z>~0.3 for all stellar masses. As in the models, however, there is a high correlation r(k) between matter and galaxy density on all scales, and galaxy bias is typically consistent with a deterministic bias on linear scales. Only our blue and low-mass galaxies of about 7x10^9^h_70_^-2^M_{sun}_ at z{bar}=0.51 show, contrary to the models, a weak tendency towards a stochastic bias on linear scales where rls=0.75+/-0.14(stat.)+/-0.06(sys.). This result is of interest for cosmological probes, such as EG, that rely on a deterministic galaxy bias. We provide Monte Carlo realisations of posterior constraints for b(k) and r(k) in CFHTLenS for every galaxy sample in this paper at the CDS.
