- ID:
- ivo://CDS.VizieR/J/MNRAS/496/2663
- Title:
- Canes Venatici I images with LOFAR
- Short Name:
- J/MNRAS/496/2663
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Dwarf galaxies are dark matter-dominated and therefore promising targets for the search for weakly interacting massive particles (WIMPs), which are well-known candidates for dark matter. Annihilation of WIMPs produce ultra-relativistic cosmic-ray electrons and positrons that emit synchrotron radiation in the presence of magnetic fields. For typical magnetic field strengths (few G) and O(GeV-TeV) WIMP masses (and thus typical electron energies of the same order) this emission peaks at hundreds of MHz. Here, we use the non-detection of 150-MHz radio continuum emission from the dwarf spheroidal galaxy 'Canes Venatici I' with the LOw-Frequency ARray (LO-FAR) to derive constraints on the annihilation cross section of WIMPs into primary electron-positron and other fundamental particle-antiparticle pairs. In this first-of-its-kind LOFAR study, we obtain new constraints on annihilating WIMP dark matter (DM). Using conservative estimates for the magnetic field strengths and diffusion coefficients, we obtain limits that are comparable with those by the Fermi Large Area Telescope (Fermi-LAT) using gamma-ray observations. Assuming s-wave annihilation and WIMPs making up 100% of the DM density, our limits exclude several thermal WIMP realisations in the [2, 20]-GeV mass range. A more ambitious multi-wavelength and multi-target LOFAR study could improve these limits by a few orders of magnitude.
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Search Results
- ID:
- ivo://CDS.VizieR/I/219
- Title:
- Cape AC Zone Data Reduced to ACRS
- Short Name:
- I/219
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The U.S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue (AC) using a modern reference system, the ACRS, which represents the system of the FK5. The data from the Cape Zone, whose plates are centered between declinations -41 and -51 degrees (eq. 1900), have been analyzed for scale, rotation, tilt, coma, magnitude equation, radial distortion and distortions introduced by the use of reseaux in the Carte du Ciel program. The result is a positional catalog of over 544,000 stars on eq. J2000.0, epoch of observation. Additionally, all stars have been matched with the Tycho Input Catalog (revised); those numbers have been added for additional identification purposes.
- ID:
- ivo://CDS.VizieR/I/116
- Title:
- Cape Photographic Catalog 1950.0 (CPC)
- Short Name:
- I/116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog includes most of the stars from the 1900.0 Cordoba Zone Catalogues B and C in the zone -30 deg. -35 deg. at the equinox of 1925.0. Some of the fainter Cordoba stars have been omitted in the rather crowded regions in the Milky Way. The aim was to provide accurate places for an average of 9 to 10 stars per square degree as a reference for a rereduction of the AG positions. Most of the stars have visual magnitudes between 7 and 10. Positions and proper motions have been supplied from the General Catalogue for those stars that were too bright for accurate measurement on photographic plates. The positions are on the FK3 system for the equinox of 1950.0. The probable errors of the positions are nominally +/- 0.15" in both right ascension and declination. That of the proper motions should not exceed +/- 1.4"/century, or +/-14 in the units in which the proper motions expressed in arc are given in the catalog.
- ID:
- ivo://CDS.VizieR/I/85
- Title:
- Cape Photographic Catalogue 2
- Short Name:
- I/85
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains the provisional positions for 51018 stars in the Cape zone -40 deg. to -52 deg., on the FK4 system for the equinox 1950.0. The internal mean error of a single coordinate obtained from the mean of r=four plates is estimated to be less than +/- 0.1" at the mean epoch of observation, about 1962. The systematic deviation from the FK4 system in a small area is probably also about +/-0.1". New proper motions have been determined for 22731 stars which are also in the Smithsonian Astrophysical Observatory (SAO) catalogue; the formal mean error of an annual proper motion in each coordinate is about +/-0.004"/a.
- ID:
- ivo://CDS.VizieR/J/A+A/642/A115
- Title:
- CARMENES input catalogue of M dwarfs. V.
- Short Name:
- J/A+A/642/A115
- Date:
- 02 Mar 2022 00:04:08
- Publisher:
- CDS
- Description:
- The relevance of M dwarfs in the search for potentially habitable Earth-size planets has grown significantly in the last years. In our on-going effort of comprehensively and accurately characterising confirmed and potential planet-hosting M dwarfs, in particular for the CARMENES survey, we have carried out a comprehensive multi-band photometric analysis involving spectral energy distributions, luminosities, absolute magnitudes, colours, and spectral types, from which we have derived basic astrophysical parameters. We have carefully compiled photometry in 20 passbands from the far-ultraviolet to the mi-infrared, and combined it with the latest parallactic distances and close-multiplicity information, mostly from Gaia DR2, of a sample of 2479 K5 V to L8 stars and ultracool dwarfs, including 2210 nearby, bright, M dwarfs. For that, we have made extensive use of Virtual Observatory tools. We have homogeneously computed accurate bolometric luminosities, effective temperatures of 1843 single stars, derived their radii and masses, studied the impact of metallicity, and compared our results with the literature. The over 40 000 individually-inspected magnitudes, together with the basic data and derived parameters of the stars, one by one and averaged by spectral type, have been made public to the astronomical community. In addition, we have reported 40 new close multiple systems and candidates (rho<3.3-arcsec) and 36 overluminous stars that are assigned to young Galactic populations. In the new era of exoplanet searches around M dwarfs via transit (e.g., TESS, PLATO) and radial velocity (e.g., CARMENES, NIRPS+HARPS), this work is of fundamental importance for stellar and, thus, planetary parameter determination.
- ID:
- ivo://CDS.VizieR/J/other/Ap/41.1
- Title:
- Catalog of barred galaxies
- Short Name:
- J/other/Ap/41.1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A catalog of barred spiral galaxies of types SB and SAB with B_T_=<13.5 and DE>-10{deg} has been compiled. Some parameters of these galaxies are given.
- ID:
- ivo://CDS.VizieR/I/16
- Title:
- Catalog of 3356 Faint Stars, 1950
- Short Name:
- I/16
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog of 3356 faint stars was derived from meridian circle observations at the Bergedorf and Heidelberg Observatories. The positions are given for the equinox 1950 on the FK3 system. The stars are mainly between 8.0 and 10.0 visual magnitude. A few are brighter than 8.0 mag. The lower limit in brightness resulted from the visibility of the stars.
- ID:
- ivo://CDS.VizieR/J/MNRAS/434/1765
- Title:
- Catalog of galaxies around PKS 0405-123
- Short Name:
- J/MNRAS/434/1765
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new absorption-line analysis and new galaxy survey data obtained for the field around PKS 0405-123 at z_QSO_=0.57. Combining previously known OVI absorbers with new identifications in the higher S/N ultraviolet (UV) spectra obtained with the Cosmic Origins Spectrograph, we have established a sample of 7 OVI absorbers and 12 individual components at z=0.0918-0.495 along the sightline towards PKS 0405-123. We complement the available UV absorption spectra with galaxy survey data that reach 100 percent completeness at projected distances {rho}<200kpc of the quasar sightline for galaxies as faint as 0.1L* (0.2L*) out to redshifts of z~0.35 (z~0.5). The high level of completeness achieved at faint magnitudes by our survey reveals that OVI absorbers are closely associated with gas-rich environments containing at least one low-mass, emission-line galaxy. An intriguing exception is a strong OVI system at z~0.183 that does not have a galaxy found at {rho}<4Mpc, and our survey rules out the presence of any galaxies of L>0.04L* at {rho}<250kpc and any galaxies of L>0.3L* at {rho}<1Mpc. We further examine the galactic environments of OVI absorbers and those 'Ly{alpha}-only' absorbers with neutral hydrogen column density log N(HI)<13.6 and no detectable OVI absorption features. The Ly{alpha}-only absorbers serve as a control sample in seeking the discriminating galactic features that result in the observed Ovi absorbing gas at large galactic radii. We find a clear distinction in the radial profiles of mean galaxy surface brightness around different absorbers. Specifically, Ovi absorbers are found to reside in regions of higher mean surface brightness at {rho}<~500kpc ({Delta}{mu}_R_~+5magMpc^-2^ relative to the background at {rho}>500kpc), while only a mild increase in galaxy surface brightness is seen at small {rho} around Ly{alpha}-only absorbers ({Delta}{mu}_R_~+2magMpc^-2^). The additional insights gained from our deep galaxy survey demonstrate the need to probe the galaxy populations to low luminosities in order to better understand the nature of the absorbing systems.
- ID:
- ivo://CDS.VizieR/VII/140
- Title:
- Catalog of Galaxies Behind the Milky Way
- Short Name:
- VII/140
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog, giving about 7000 galaxies behind the Milky Way between l = 210 degrees and 250 degrees, represents a systematic search for galaxies by means of 32 film copies of the UK Schmidt Southern Infrared Atlas on the Milky Way covering about 900 square degrees. In the search galaxies with apparent sizes greater than 0.1 mm on film (6.7 arcsec in size) were detected by visual inspection. The material and procedure of search are described as well as the detectability of galaxies in paper I and paper II appended before Vol. 1 and Vol. 2 of the catalog, respectively, which have been published in Publ. Astron. Soc. Japan, Vol. 42 (1990) and Vol. 43 (1991). The parameters of catalogued galaxies are also explained in paper I. Cross-identifications with other catalogs are shown in the last column. The search was performed by undergraduate students of a galactic astronomy program in Department of Astronomy, Kyoto University, in 1988 and 1989. Since the main researchers changed from the search in 1988 (Vol. 1) to that in 1989 (Vol. 2), a surface brightness level determining the extents of galaxy images somewhat differs between Vol. 1 and Vol. 2, yielding a difference of mean number densities of the detected galaxies between Vol. 1 and Vol. 2. The difference is examined in paper II. The detectability of galaxies, especially of smallest galaxies, increased in the overlap zones of adjacent fields of the Atlas; the effects are discussed in a paper (Yamada and Saito 1991, to appear in Publ. Astron. Soc. Japan, Vol. 43). In spite of such inhomogeneities in search for galaxies, the catalog is useful as a finding list of bright galaxies, peculiar galaxies, and nearby clusters of galaxies in the region behind the Milky Way. The machine-readable version of the catalog has been made through efforts of Mr. Shogo Nishida, Mr. Tadafumi Takata, and Professor Shiro Nishimura. This will be distributed upon request from Astronomical Data Analysis Center of the National Astronomical Observatory of Japan and other astronomical data centers. This work was supported by the Grant-in-Aid for General Scientific Research (01420002) of the Japanese Ministry of Education, Science, and Culture. June 1991 Mamoru Saito
- ID:
- ivo://CDS.VizieR/J/A+A/412/633
- Title:
- Catalog of high and low SB disk galaxies
- Short Name:
- J/A+A/412/633
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have compiled and homogenized a sample of high and low SB disk galaxies with available photometry in the B and K bands, velocity line-widths and HI integral fluxes. Several parameters that trace the luminous, baryonic and dark matter contents were inferred. We investigated how these parameters do vary with different galaxy properties, and confronted the results with predictions of galaxy evolutionary models in the context of the {Lambda} Cold Dark Matter (LCDM) cosmogony. The fractions of dark, baryonic and luminous matter inside disk sizes (for observations and models) depend mainly on the disk surface density (or brightness). We have not found significant correlations of these fractions on galaxy scale or luminosity, contrary to what has been reported in previous works, based on the analysis of rotation curve shapes. We discuss this difference and state the importance to solve the controversy. The broad agreement between the models and observations presented here favors the LCDM scenario. However, the excess of dark matter inside the optical region of disk galaxies remains as the main difficulty.