- ID:
- ivo://nasa.heasarc/cepaxmm
- Title:
- Cepheus A SFR XMM-Newton X-Ray Point Source Catalog
- Short Name:
- CEPAXMM
- Date:
- 25 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Cepheus A is a star formation region (SFR) at a distance of ~ 730 pc consisting of two main H II regions, Cep A East and Cep A West. Cep A was observed with the EPIC cameras of the XMM-Newton observatory on 2003 August 23 for 43.9ks. In this observation, X-rays from both components of Cep A, East and West, were discovered by XMM-Newton, as well as from the Herbig-Haro object HH 168, which joins the ranks of other energetic H-H objects that are sources of temperature T >= 10<sup>6</sup> K X-ray emission. A total of 102 distinct X-ray sources were detected in this 44 ks observation, many presumed to be pre-main-sequence stars on the basis of the reddening of their optical and IR counterparts, the latter being found by matching the positions of the 102 X-ray sources with objects in the USNO-B1.0 (Monet et al. 2003, AJ, 125, 984) and Two Micron All Sky Survey (2MASS) catalogs using a 2.5" matching radius. The authors performed source detection on all the XMM-Newton data in two energy bands: 0.2 - 1 keV ("soft") and 1 - 10 keV ("hard"). They detected 24 soft sources and 85 hard sources. Seven of the sources appear in both bands, where the criterion for a match between the bands is a positional offset of < 2.5 arcseconds. Thus, the total number of distinct X-ray sources detected (and listed in this table) is 102. This table was created by the HEASARC in July 2007 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/626/272">CDS Catalog J/ApJ/626/272</a> file table2.dat. This is a service provided by NASA HEASARC .
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/602/A8
- Title:
- Cepheus E CO, OH and OI spectra
- Short Name:
- J/A+A/602/A8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Protostellar jets and outflows are key features of the star-formation process, and primary processes of the feedback of young stars on the interstellar medium. Understanding the underlying shocks is necessary to explain how jet and outflow systems are launched, and to quantify their chemical and energetic impacts on the surrounding medium. We performed a high-spectral resolution study of the [OI]63um emission in the outflow of the intermediate-mass Class 0 protostar Cep E-mm. The goal is to determine the structure of the outflow, to constrain the chemical conditions in the various components, and to understand the nature of the underlying shocks, thus probing the origin of the mass-loss phenomenon. We present observations of the OI ^3^P_1_ -> ^3^P_2_, OH between ^2^{Pi}_1/2_ J=3/2 and J=1/2 at 1837.8GHz, and CO (16-15) lines with the GREAT receiver onboard SOFIA towards three positions in the Cep E protostellar outflow: Cep E-mm (the driving protostar), Cep E-BI (in the southern lobe), and Cep E-BII (the terminal position in the southern lobe).
- ID:
- ivo://CDS.VizieR/J/ApJS/115/59
- Title:
- Cepheus flare molecular clouds
- Short Name:
- J/ApJS/115/59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results of an objective prism Schmidt survey are combined with IRAS survey data in order to assess the star-forming activity in the Cepheus Flare, a nearby giant molecular cloud complex at ~15{deg} above the Galactic equator. The distribution of absorbing matter along the line of sight was also studied. The Wolf diagrams, displaying the cumulative distribution of field star distance moduli, show that the interstellar matter in this region is concentrated at three characteristic distances: 200, 300, and 450pc. The three components, though partly overlapping, can be separated along the Galactic latitude. Within the area of the Cepheus Flare, distances are determined for 14 Lynds dark clouds and for some other clouds.
- ID:
- ivo://CDS.VizieR/J/A+A/573/A19
- Title:
- Cep OB2 Herschel/PACS view
- Short Name:
- J/A+A/573/A19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The CepOB2 region, with its two intermediate-aged clusters Tr37 and NGC7160, is a paradigm of sequential star formation and an ideal site for studies of protoplanetary disk evolution. We use Herschel data to study the protoplanetary disks and the star formation history of the region. Herschel/PACS observations at 70 and 160{mu}m probe the disk properties (mass, dust sizes, structure) and the evolutionary state of a large number of young stars. Far-IR data also trace the remnant cloud material and small-scale cloud structure. We detect 95 protoplanetary disks at 70{mu}m, 41 at 160{mu}m, and obtain upper limits for more than 130 objects. The detection fraction at 70{mu}m depends on the spectral type (88% for K4 or earlier stars, 17% for M3 or later stars) and on the disk type (~50% for full and pre-transitional disks, ~35% for transitional disks, no low-excess/depleted disks detected). Non-accreting disks are not detected, suggesting significantly lower masses. Accreting transition and pre-transition disks have systematically higher 70{mu}m excesses than full disks, suggestive of more massive, flared and/or thicker disks. Herschel data also reveal several mini-clusters in Tr37, which are small, compact structures containing a few young stars surrounded by nebulosity. Far-IR data are an excellent probe of the evolution of disks that are too faint for sub-millimetre observations. We find a strong link between far-IR emission and accretion, and between the inner and outer disk structure. Herschel confirms the dichotomy between accreting and non-accreting transition disks. Accretion is a powerful measure of global disk evolution: substantial mass depletion and global evolution need to occur to shut down accretion in a protoplanetary disk, even if the disk has inner holes. Disks likely follow different evolutionary paths: low disk masses do not imply opening inner holes, and having inner holes does not require low disk masses. The mini-clusters reveal multi-episodic star formation in Tr37. The long survival of mini-clusters suggest that they formed from the fragmentation of the same core. Their various morphologies favour different formation/triggering mechanisms acting within the same cluster. The beads-on-a-string structure in one mini-cluster is consistent with gravitational fragmentation or gravitational focusing, acting on very small scales (solar-mass stars in ~0.5pc filaments). Multi-episodic star formation could also produce evolutionary variations between disks in the same region. Finally, Herschel also unveils what could be the first heavy mass loss episode of the O6.5 star HD 206267 in Tr 37.
- ID:
- ivo://CDS.VizieR/J/A+AS/134/401
- Title:
- 4C equatorial sample VLA observations. II.
- Short Name:
- J/A+AS/134/401
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- VLA observations at 4.9GHz are given for 144 steep-spectrum 4C sources whose declinations are between -4{deg} and +4{deg} and whose angular sizes are smaller than 30arcsec. The paper contains 150 maps (VLA and 6 MERLIN observations at 1420 or 1658MHz) which are not included here.
- ID:
- ivo://CDS.VizieR/J/MNRAS/443/2815
- Title:
- Cerro Armazones spectroscopy of F dwarfs
- Short Name:
- J/MNRAS/443/2815
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a spectroscopic survey of a sample of F stars that have not yet been searched for planets. The observations of 187 stars obtained with the Bochum Echelle Spectrographic Observer of the Cerro Armazones Observatory were aimed at nearby (closer than 70pc) main-sequence stars without sufficient archive ([fiber-fed extended range optical spectrograph (FEROS)/high accuracy radial velocity planet search (HARPS)]) spectroscopy. The primary goal of the survey was to select the best candidates for radial-velocity searches of extrasolar planets. The spectra were analysed using the broadening-function technique, the method of choice for rapid rotators later than about A5. The analysis was focused not only at the determination of projected rotational velocity (defining precision of radial-velocity determination), but also at the detection of previously unknown spectroscopic binaries/multiples or stars showing strong line asymmetries. 12 previously unknown spectroscopic binaries/triples were detected. For all observed targets the spectral type was determined. About 140 stars are rotating faster than the resolution limit of 10km/s sampling the onset of convection and slow rotation at mid-F spectral types in great detail. Radial-velocity precision of the data (about 100m/s) is insufficient to detect planets but could indicate most SB1 systems with stellar companions. As there are already 2-3 observations per object for these newly detected binary stars, only a few additional follow-up observations will be needed to obtain constraints on orbital parameters. We identified a sample of 68 bright F-type dwarf stars which are perfect targets for future planet searches. They rotate moderately or slowly and do not show any sign of binarity, pulsations, or surface activity.
- ID:
- ivo://CDS.VizieR/J/MNRAS/423/2436
- Title:
- CES ultra deep catalogue of galaxy structures
- Short Name:
- J/MNRAS/423/2436
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents a large sample of intermediate- to high-redshift galaxy groups and clusters detected using a fully automated search in the Cosmic Evolution Survey field. The detection algorithm is based on density peak extraction from a density distribution sampled using Voronoi tessellation within overlapping slices in the photometric redshift space. The cluster catalogue contains 1780 structures covering the redshift range 0.2<z<3.0, spanning three orders of magnitude in luminosity (10^8^<L_4_<5x10^11^L_{sun}_) and richness from eight to hundreds of galaxies. All clusters at z>0.4 and many even below this threshold show very prominent substructure indicating that z~0.4 marks the slow emergence of virialized clusters in this field in agreement with published findings for other regions of the sky. The redshift distribution of detected structures shows strong variations with prominent peaks suggesting the presence of large-scale structures across the whole range covered by this catalogue. Supercluster candidates have been identified at redshifts z=0.35, 0.72, 0.94, 1.12, 1.27, 1.45, 2.0 and 2.52. At z=2.9 we identified a compact agglomeration of galaxy groups and clusters suggesting the presence of another supercluster-like structure which has been the highest redshift candidate so far. Out of the nine supercluster candidates found in this study, six are new detections.
3328. Cetus dSph RR Lyrae
- ID:
- ivo://CDS.VizieR/J/MNRAS/422/89
- Title:
- Cetus dSph RR Lyrae
- Short Name:
- J/MNRAS/422/89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the variable star content of the isolated, Local Group, dwarf spheroidal (dSph) galaxy Cetus. Multi-epoch, wide-field images collected with the Very Large Telescope/Visible Multiobject Spectrograph camera allowed us to detect 638 variable stars (630 RR Lyrae stars and eight anomalous Cepheids), 475 of which are new detections. We present a full catalogue of periods, amplitudes and mean magnitudes.
- ID:
- ivo://CDS.VizieR/J/A+A/618/A122
- Title:
- Cetus dSph stellar chemo-kinematics
- Short Name:
- J/A+A/618/A122
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Cetus is an isolated, dwarf spheroidal (dSph) galaxy at a distance of 755kpc. In order to quantify its stellar chemo-kinematical properties, we observed individual red giants branch stars in Cetus with the Very Large Telescope (VLT) FORS2 instrument, in Mask eXchange Unit (MXU) configuration. The kinematic analysis shows that Cetus is a mainly pressure-supported ({sigma}_v_=11.0^+1.6^_-1.3_km/s), dark-matter-dominated system (M_1/2_/L_V_=23.9^+9.7^_-8.9_M_{sun}_/L_{sun}_) with no significant signs of internal rotation. We find Cetus to be a metal-poor system with a significant metallicity spread (median [Fe/H]=-1.71dex, median-absolute-deviation =0.49dex), as expected for its stellar mass. We report the presence of a mild metallicity gradient compatible with those found in other dSphs of the same luminosity; we trace the presence of a stellar population gradient also in the spatial distribution of stars in different evolutionary phases in ancillary photometric data. There are tentative indications of two chemo-kinematically distinct sub-populations, with the more metal-poor stars showing a hotter kinematics than the metal-richer ones. Our results add Cetus to the growing scatter in stellar-dark matter halo properties in low-mass galactic systems. The presence of a metallicity gradient akin to those found in similar systems inhabiting different environments may hint at metallicity gradients in Local Group early-type dwarfs being driven by internal mechanisms.
- ID:
- ivo://CDS.VizieR/J/A+A/640/A69
- Title:
- 3C 279 Event Horizon Telescope imaging
- Short Name:
- J/A+A/640/A69
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 3C 279 is an archetypal blazar with a prominent radio jet that show broadband flux density variability across the entire electromagnetic spectrum. We use an ultra-high angular resolution technique - global Very Long Baseline Interferometry (VLBI) at 1.3mm (230GHz) - to resolve the innermost jet of 3C 279 in order to study its fine-scale morphology close to the jet base where highly variable gamma-ray emission is thought to originate, according to various models. The source was observed during four days in April 2017 with the Event Horizon Telescope (EHT) at 230 GHz, including the phased Atacama Large Millimeter/submillimeter Array (ALMA), at an angular resolution of ~20uarcsec (at a redshift of z=0.536 this corresponds to ~0.13pc, ~1700 Schwarzschild radii with a black hole mass M_BH_=8x10^8^M_{sun}_). Imaging and model-fitting techniques were applied to the data to parameterize the fine-scale source structure and its variation. We find a multicomponent inner jet morphology with the northernmost component elongated perpendicular to the direction of the jet, as imaged at longer wavelengths. The elongated nuclear structure is consistent on all four observing days and across different imaging methods and model-fitting techniques, and therefore appears robust. Owing to its compactness and brightness, we associate the northern nuclear structure as the VLBI "core". This morphology can be interpreted as either a broad resolved jet base or a spatially bent jet. We also find significant day-to-day variations in the closure phases, which appear most pronounced on the triangles with the longest baselines. Our analysis shows that this variation is related to a systematic change of the source structure. Two inner jet components move non-radially at apparent speeds of ~15c and ~20c (~1.3 and ~1.7uarcsec/day, respectively), which more strongly supports the scenario of traveling shocks or instabilities in a bent, possibly rotating jet. The observed apparent speeds are also coincident with the 3C 279 large-scale jet kinematics observed at longer (cm) wavelengths, suggesting no significant jet acceleration between the 1.3mm core and the outer jet. The intrinsic brightness temperature of the jet components are <~10^10^K, a magnitude or more lower than typical values seen at >=7mm wavelengths. The low brightness temperature and morphological complexity suggest that the core region of 3C279 becomes optically thin at short (mm) wavelengths.
