- ID:
- ivo://CDS.VizieR/J/MNRAS/414/2005
- Title:
- Cosmic flows observations
- Short Name:
- J/MNRAS/414/2005
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The neutral hydrogen properties of 1822 galaxies are being studied with the Green Bank 100-m and the Parkes 64-m telescopes as part of the 'Cosmic Flows' programme. Observed parameters include systemic velocities, profile linewidths and integrated fluxes. The linewidth information can be combined with the optical and infrared photometry to obtain distances. The 1822 HI observations complement an inventory of archives.
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- ID:
- ivo://CDS.VizieR/J/ApJ/896/3
- Title:
- Cosmicflows-4: Tully-Fisher relation calibrations
- Short Name:
- J/ApJ/896/3
- Date:
- 07 Mar 2022 07:21:25
- Publisher:
- CDS
- Description:
- This study is a part of the Cosmicflows-4 project with the aim of measuring the distances of more than ~10000 spiral galaxies in the local universe up to ~15000km/s. New HI line width information has come primarily from the Arecibo Legacy Fast ALFA Survey. Photometry of our sample galaxies has been carried out in optical (SDSS u, g, r, i, and z) and infrared (WISE W1 and W2) bands. Inclinations have been determined using an online graphical interface accessible to a collaboration of citizen scientists. Galaxy distances are measured based on the correlation between the rotation rate of spirals and their absolute luminosity, known as the Tully-Fisher relation (TFR). In this study, we present the calibration of the TFR using a subsample of ~600 spirals located in 20 galaxy clusters. Correlations among such observables as color, surface brightness, and relative HI content are explored in an attempt to reduce the scatter about the TFR with the goal of obtaining more accurate distances. A preliminary determination of the Hubble constant from the distances and velocities of the calibrator clusters is H0=76.0+/-1.1(stat.)+/-2.3(sys.)km/s/Mpc.
- ID:
- ivo://CDS.VizieR/J/A+A/631/A40
- Title:
- Cosmic Horseshoe (J1148+1930) Ha and OIII spectra
- Short Name:
- J/A+A/631/A40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a detailed analysis of the inner mass structure of the Cosmic Horseshoe (J1148+1930) strong gravitational lens system observed with the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3). In addition to the spectacular Einstein ring, this systems shows a radial arc. We obtained the redshift of the radial arc counter image z_s,r_=1.961+/-0.001 from Gemini observations. To disentangle the dark and luminous matter, we consider three different profiles for the dark matter distribution: a power-law profile, the NFW, and a generalized version of the NFW profile. For the luminous matter distribution, we base it on the observed light distribution that is fitted with three components: a point mass for the central light component resembling an active galactic nucleus, and the remaining two extended light components scaled by a constant M/L. To constrain the model further, we include published velocity dispersion measurements of the lens galaxy and perform a self-consistent lensing and axisymmetric Jeans dynamical modeling. Our model fits well to the observations including the radial arc, independent of the dark matter profile. Depending on the dark matter profile, we get a dark matter fraction between 60% and 70%. With our composite mass model we find that the radial arc helps to constrain the inner dark matter distribution of the Cosmic Horseshoe independently of the dark matter profile.
- ID:
- ivo://CDS.VizieR/J/ApJ/863/119
- Title:
- Cosmic-ray nuclei studies with Voyager, ACE & AMS-02
- Short Name:
- J/ApJ/863/119
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The acceleration of cosmic-ray particles and their propagation in the Milky Way and the heliosphere tangle with each other, leading to complexity and degeneracy of the modeling of Galactic cosmic rays (GCRs). The recent measurements of the GCR spectra by Voyager-1 from outside of the heliosphere gave the first direct observation of GCRs in the local interstellar (LIS) environment. Together with the high-precision data near the Earth taken by the Advanced Composition Explorer (ACE) and AMS-02, we derive the LIS spectra of helium, lithium, beryllium, boron, carbon, and oxygen nuclei from a few MeV/n to TeV/n, using a non-parameterization method. These LIS spectra are helpful in further studying the injection and propagation parameters of GCRs. The nearly 20 years of data recorded by ACE are used to determine the solar modulation parameters over solar cycles 23 and 24, based on the force-field approximation. We find general agreements of the modulation potential with the results inferred from neutron monitors and other cosmic-ray data.
- ID:
- ivo://CDS.VizieR/J/ApJ/854/183
- Title:
- Cosmic-ray nucleosynthesis of p-nuclei
- Short Name:
- J/ApJ/854/183
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the cosmic-ray nucleosynthesis (CRN) of proton-rich stable nuclides (p-nuclides). We calculate the cosmic-ray (CR) energy spectra of heavy nuclides with mass number A=[74,209], taking into account the detailed nuclear spallation, decay, energy loss, and escape from the Galaxy during the CR propagation. We adopt the latest semiempirical formula SPACS (Schmitt+ 2014PhRvC..90f4605S) for the spallation cross sections and the latest data on nuclear decay. Effective electron-capture decay rates are calculated using the proper cross sections for recombination and ionization in the whole CR energy region. Calculated CR spectral shapes vary for different nuclides. Abundances of proton-rich unstable nuclides increase in CRs with increasing energy relative to those of other nuclides. Yields of the primary and secondary spallation processes and differential yields from respective seed nuclides are calculated. We find that the CR energy region of <=O(100)MeV/nucleon predominantly contributes to the total yields. The atomic cross sections in the low-energy range adopted in this study are then necessary. Effects of CRN on the Galactic chemical evolution of p-nuclides are calculated. Important seed nuclides are identified for respective p-nuclides. The contribution of CRN is significant for ^180m^Ta, accounting for about 20% of the solar abundance. About 87% of the ^180m^Ta CRN yield can be attributed to the primary process. The most important production routes are reactions of ^181^Ta, ^180^Hf, and ^182^W. CRN yields of other p-nuclides are typically about O(10^-4^-10^-2^) of solar abundances.
- ID:
- ivo://CDS.VizieR/J/MNRAS/438/3465
- Title:
- Cosmic web filaments in the SDSS
- Short Name:
- J/MNRAS/438/3465
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The main feature of the spatial large-scale galaxy distribution is its intricate network of galaxy filaments. This network is spanned by the galaxy locations that can be interpreted as a three-dimensional point distribution. The global properties of the point process can be measured by different statistical methods, which, however, do not describe directly the structure elements. The morphology of the large scale structure, on the other hand, is an important property of the galaxy distribution. Here we apply an object point process with interactions (the Bisous model) to trace and extract the filamentary network in the presently largest galaxy redshift survey, the Sloan Digital Sky Survey (SDSS). We search for filaments in the galaxy distribution that have a radius of about 0.5Mpc/h. We divide the detected network into single filaments and present a public catalogue of filaments. We study the filament length distribution and show that the longest filaments reach the length of 60Mpc/h. The filaments contain 35-40% of the total galaxy luminosity and they cover roughly 5-8% of the total volume, in good agreement with N-body simulations and previous observational results.
- ID:
- ivo://CDS.VizieR/J/ApJ/837/16
- Title:
- Cosmic web of galaxies in the COSMOS field
- Short Name:
- J/ApJ/837/16
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use a mass complete (log(M/M_{sun}_)>=9.6) sample of galaxies with accurate photometric redshifts in the COSMOS field to construct the density field and the cosmic web to z=1.2. The comic web extraction relies on the density field Hessian matrix and breaks the density field into clusters, filaments, and the field. We provide the density field and cosmic web measures to the community. We show that at z<~0.8, the median star formation rate (SFR) in the cosmic web gradually declines from the field to clusters and this decline is especially sharp for satellites (~1dex versus ~0.5dex for centrals). However, at z>~0.8, the trend flattens out for the overall galaxy population and satellites. For star-forming (SF) galaxies only, the median SFR is constant at z>~0.5 but declines by ~0.3-0.4dex from the field to clusters for satellites and centrals at z<~0.5. We argue that for satellites, the main role of the cosmic web environment is to control their SF fraction, whereas for centrals, it is mainly to control their overall SFR at z<~0.5 and to set their fraction at z>~0.5. We suggest that most satellites experience a rapid quenching mechanism as they fall from the field into clusters through filaments, whereas centrals mostly undergo a slow environmental quenching at z<~0.5 and a fast mechanism at higher redshifts. Our preliminary results highlight the importance of the large-scale cosmic web on galaxy evolution.
- ID:
- ivo://CDS.VizieR/J/A+A/584/A26
- Title:
- Cosmography of OB stars in the solar neighbourhood
- Short Name:
- J/A+A/584/A26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We construct a 3D map of the spatial density of OB stars within 500pc from the Sun using the Hipparcos catalogue and find three large-scale stream-like structures that allow a new view on the solar neighbourhood. The spatial coherence of these blue streams and the monotonic age sequence over hundreds of parsecs suggest that they are made of young stars, similar to the young streams that are conspicuous in nearby spiral galaxies. The three streams are 1) the Scorpius to Canis Majoris stream, covering 350pc and 65Myr of star formation history; 2) the Vela stream, encompassing at least 150pc and 25Myr of star formation history; and 3) the Orion stream, including not only the well-known Orion OB1abcd associations, but also a large previously unreported foreground stellar group lying only 200pc from the Sun. The map also reveals a remarkable and previously unknown nearby OB association, between the Orion stream and the Taurus molecular clouds, which might be responsible for the observed structure and star formation activity in this cloud complex. This new association also appears to be the birthplace of Betelgeuse, as indicated by the proximity and velocity of the red giant. If this is confirmed, it would solve the long-standing puzzle of the origin of Betelgeuse. The well-known nearby star-forming low-mass clouds, including the nearby T and R associations Lupus, Cha, Oph, CrA, Taurus, Vela R1, and various low-mass cometary clouds in Vela and Orion, appear in this new view of the local neighbourhood to be secondary star formation episodes that most likely were triggered by the feedback from the massive stars in the streams. We also recover well-known star clusters of various ages that are currently cruising through the solar neighbourhood. Finally, we find no evidence of an elliptical structure such as the Gould belt, a structure we suggest is a 2D projection effect, and not a physical ring.
- ID:
- ivo://CDS.VizieR/J/A+A/627/A137
- Title:
- Cosmology from galaxy lensing and clustering
- Short Name:
- J/A+A/627/A137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The combination of Galaxy-Galaxy Lensing (GGL) and Redshift Space Distortion of galaxy clustering (RSD) is a privileged technique to test General Relativity predictions, and break degeneracies between the growth rate of structure parameter f and the amplitude of the linear power-spectrum {sigma}8. We perform a joint GGL and RSD analysis on 250 sq. degrees using shape catalogues from CFHTLenS and CFHT-Stripe 82, and spectroscopic redshifts from the BOSS CMASS sample. We adjust a model that includes non-linear biasing, RSD and Alcock-Paczynski effects. We find f(z=0.57)=0.95+/-0.23, {sigma}8(z=0.57)=0.55+/-0.07 and {OMEGA}m=0.31+/-0.08, in agreement with Planck cosmological results 2018. We also estimate the probe of gravity E_G_=0.43+/-0.10 in agreement with {LAMBDA}CDM-GR predictions of E_G_=0.40. This analysis reveals that RSD efficiently decreases the GGL uncertainty on {OMEGA}m by a factor of 4, and by 30% on {sigma}8. We use an N-body simulation supplemented by an abundance matching prescription for CMASS to build a set of overlapping lensing and clustering mocks. Together with additional spectroscopic data, this helps us to quantify and correct several systematic errors, such as photometric redshifts. We make our mock catalogues available on the Skies and Universe database.
- ID:
- ivo://CDS.VizieR/J/ApJ/696/1195
- Title:
- COSMOS AGN spectroscopic survey. I.
- Short Name:
- J/ApJ/696/1195
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical spectroscopy for an X-ray and optical flux-limited sample of 677 XMM-Newton selected targets covering the 2deg^2^ Cosmic Evolution Survey field, with a yield of 485 high-confidence redshifts. The majority of the spectra were obtained over three seasons (2005-2007) with the Inamori Magellan Areal Camera and Spectrograph instrument on the Magellan (Baade) telescope. We also include in the sample previously published Sloan Digital Sky Survey spectra and supplemental observations with MMT/Hectospec. We detail the observations and classification analyses. The survey is 90% complete to flux limits of f_0.5-10keV_>8x10^-16-^erg/cm^2^/s and i^+^_AB_<22, where over 90% of targets have high-confidence redshifts. Making simple corrections for incompleteness due to redshift and spectral type allows for a description of the complete population to i^+^_AB_<23. The corrected sample includes a 57% broad emission line (Type 1, unobscured) active galactic nucleus (AGN) at 0.13<z<4.26, 25% narrow emission line (Type 2, obscured) AGN at 0.07<z<1.29, and 18% absorption line (host-dominated, obscured) AGN at 0<z<1.22 (excluding the stars that made up 4% of the X-ray targets). We show that the survey's limits in X-ray and optical fluxes include nearly all X-ray AGNs (defined by L_0.5-10keV_>3x10^42^erg/s) to z<1, of both optically obscured and unobscured types.