- ID:
- ivo://CDS.VizieR/J/A+A/575/A119
- Title:
- HARPS RV and stellar activity
- Short Name:
- J/A+A/575/A119
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Planetary companions of a fixed mass induce reflex motions with a larger amplitude around lower-mass stars, which adds to making M dwarfs excellent targets for extra-solar planet searches. The most recent velocimeters with a stability of can detect very low-mass planets out to the habitable zone of these stars. Low-mass small planets are abundant around M dwarfs, and most of the known potentially habitable planets orbit one of these cool stars. Our M-dwarf radial velocity monitoring with HARPS on the ESO 3.6m telescope at La Silla observatory makes a major contribution to this sample. We present here dense radial velocity (RV) time series for three M dwarfs observed over ~five years: GJ 3293 (0.42M_{sun}_), GJ 3341 (0.47M_{sun}_), and GJ 3543 (0.45M_{sun}_). We extracted these RVs through minimum chi^2^ -matching of each spectrum against a stack of all observed spectra for the same star that has a high S/N ratio. We then compared potential orbital signals against several stellar activity indicators to distinguish the Keplerian variations induced by planets from the spurious signals that result from rotational modulation of stellar surface inhomogeneities and from activity cycles.
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5912. HARPS-TERRA project. I.
- ID:
- ivo://CDS.VizieR/J/ApJS/200/15
- Title:
- HARPS-TERRA project. I.
- Short Name:
- J/ApJS/200/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Doppler spectroscopy has uncovered or confirmed all the known planets orbiting nearby stars. Two main techniques are used to obtain precision Doppler measurements at optical wavelengths. The first approach is the gas cell method, which consists of least-squares matching of the spectrum of iodine imprinted on the spectrum of the star. The second method relies on the construction of a stabilized spectrograph externally calibrated in wavelength. The most precise stabilized spectrometer in operation is the High Accuracy Radial velocity Planet Searcher (HARPS), operated by the European Southern Observatory in La Silla Observatory, Chile. The Doppler measurements obtained with HARPS are typically obtained using the cross-correlation function (CCF) technique. This technique consists of multiplying the stellar spectrum by a weighted binary mask and finding the minimum of the product as a function of the Doppler shift. It is known that CCF is suboptimal in exploiting the Doppler information in the stellar spectrum. Here we describe an algorithm to obtain precision radial velocity measurements using least-squares matching of each observed spectrum to a high signal-to-noise ratio template derived from the same observations. This algorithm is implemented in our software HARPS-TERRA (Template-Enhanced Radial velocity Re-analysis Application). New radial velocity measurements on a representative sample of stars observed by HARPS are used to illustrate the benefits of the proposed method. We show that, compared with CCF, template matching provides a significant improvement in accuracy, especially when applied to M dwarfs.
- ID:
- ivo://CDS.VizieR/J/A+A/523/A15
- Title:
- HARPS XXIII: RV data for the 8 targets
- Short Name:
- J/A+A/523/A15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present our HARPS radial-velocity data for eight low-activity solar-type stars belonging to the HARPS volume-limited sample: HD6718, HD8535, HD28254, HD290327, HD43197, HD44219, HD148156, and HD156411. Keplerian fits to these data reveal the presence of low-mass companions around these targets. With minimum masses ranging from 0.58 to 2.54M_{Jup}_, these companions are in the planetary mass domain. The orbital periods of these planets range from slightly less than one to almost seven years. The eight orbits presented in this paper exhibit a wide variety of eccentricities: from 0.08 to above 0.8.
- ID:
- ivo://CDS.VizieR/J/A+A/549/A109
- Title:
- HARPS XXXI. The M-dwarf sample
- Short Name:
- J/A+A/549/A109
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Searching for planets around stars with different masses helps us to assess the outcome of planetary formation for different initial conditions. The low-mass M dwarfs are also the most frequent stars in our Galaxy and potentially therefore, the most frequent planet hosts. We present observations of 102 southern nearby M dwarfs, using a fraction of our guaranteed time on the ESO/HARPS spectrograph. We observed for 460 h and gathered 1965 precise (~1-3m/s) radial velocities (RVs), spanning the period from Feb. 11, 2003 to Apr. 1, 2009.
- ID:
- ivo://CDS.VizieR/J/A+A/633/A44
- Title:
- HARPS Young Nearby Stars - YNS
- Short Name:
- J/A+A/633/A44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Young nearby stars are good candidates in the search for planets with both radial velocity (RV) and direct imaging techniques. This, in turn, allows for the computation of the giant planet occurrence rates at all separations. The RV search around young stars is a challenge as they are generally faster rotators than older stars of similar spectral types and they exhibit signatures of magnetic activity (spots) or pulsation in their RV time series. Specific analyses are necessary to characterize, and possibly correct for, this activity. Our aim is to search for planets around young nearby stars and to estimate the giant planet (GP) occurrence rates for periods up to 1000 days. We used the HARPS spectrograph on the 3.6m telescope at La Silla Observatory to observe 89 A-M young (<600Myr) stars. We used our SAFIR (Spectroscopic data via Analysis of the Fourier Interspectrum Radial velocities) software to compute the RV and other spectroscopic observables. Then, we computed the companion occurrence rates on this sample. We confirm the binary nature of HD 177171, HD 181321 and HD 186704. We report the detection of a close low mass stellar companion for HIP 36985. No planetary companion was detected. We obtain upper limits on the GP (<13M_Jup_) and BD ({in}[13;80]M_Jup_) occurrence rates based on 83 young stars for periods less than 1000 days, which are set, 2_-2_^+3^ and 1_-1_^+3^%.
5916. Harvard variables
- ID:
- ivo://CDS.VizieR/J/other/IBVS/5298
- Title:
- Harvard variables
- Short Name:
- J/other/IBVS/529
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Coordinates and identifications are presented for 726 Harvard Variable stars and suspected variables, discovered or studied by D. Hoffleit and announced in Harvard Bulletins 874, 884, 887, 901, and 902; plus 141 others, previously known, lying in the same fields.
- ID:
- ivo://CDS.VizieR/VIII/7A
- Title:
- Hat Creek High-Latitude H I Survey
- Short Name:
- VIII/7A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This survey consists of H I 21-cm spectra covering the entire northern sky with absolute Galactic latitude |b|>10 degrees and declination dec>-30degrees. The observations were made with the Hat Creek 85-foot telescope between 1968 and 1970. The individual spectra were obtained with a bank of 100 filters covering the velocity range from -92km/s to +75km/s. The velocity resolution was 2 km/sec (except at the ends of the spectra) and the beamwidth was 36arcmin. The spacing between points observed on the sky is (0.3deg/cosb) in Galactic longitude and (0.6deg) in Galactic latitude. A FITS version of the survey was derived at the Astrophysics Data Facility (NASA/GSFC) from the original catalog of spectra. The approximately 130,000 good spectra in the catalog (i.e., those with status code 1 and which have flat baselines) were interpolated to a uniform channel width in frequency, shifted as appropriate to take into account the proper central velocities, then interpolated onto a regular grid in Galactic coordinates. For the latter interpolation, the cos(b) corrections for longitude offsets were taken into account; no interpolation was done across gaps in coverage greater than 2 deg. Latitude-velocity slices were written in FITS format for each 30 arcmin of longitude. Separate files were written for the negative latitude (b < -10 deg ) and positive latitude (b > 10 deg) ranges. Slices containing no spectra, primarily negative latitude spectra in the fourth Galactic quadrant, were not written. A longitude-latitude map, integrated over all velocities, was also written in FITS format to illustrate the coverage of the individual latitude-velocity slices.
- ID:
- ivo://irsa.ipac/Herschel/Catalog/H-ATLAS/H-ATLAS_All
- Title:
- H-ATLAS All Potential Counterparts Catalog
- Short Name:
- H-ATLAS_All
- Date:
- 01 Oct 2018 20:27:20
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- The Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) is a survey of 600 deg^2 in five photometric bands - 100, 160, 250, 350 and 500 microns - with the Photoconductor Array Camera and Spectrometer (PACS) and Spectral and Photometric Imaging Receiver (SPIRE) cameras. H-ATLAS DR1 includes the survey of three fields on the celestial equator, covering a total area of 161.6 deg^2 and previously observed in the Galaxy and Mass Assembly (GAMA) spectroscopic survey. The data release main catalogue (HATLAS_DR1_CATALOGUE.FITS) contains only the 'best' candidate ID to each SPIRE source (where available). Most users will find in this catalogue everything they will need for their science purposes. A second catalogue is also available (HATLAS_DR1_CATALOGUE_ALLIDS.FITS), which contains all possible counterparts within the search radius of each SPIRE source, and provides the full LR statistics so that these may be independently analysed as the user wishes. To select only sources which have reliable optical IDs, a cut of Reliability#0.8 is recommended, although other cuts on Reliability or LR may be suitable for different purposes as discussed in Bourne et al. (2016).
- ID:
- ivo://CDS.VizieR/J/MNRAS/465/3558
- Title:
- HATLAS candidate lensed galaxies
- Short Name:
- J/MNRAS/465/3558
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a sample of 80 candidate strongly lensed galaxies with flux density above 100mJy at 500{mu}m extracted from the Herschel Astrophysical Terahertz Large Area Survey, over an area of 600deg^2^. Available imaging and spectroscopic data allow us to confirm the strong lensing in 20 cases and to reject it in one case. For other eight objects, the lensing scenario is strongly supported by the presence of two sources along the same line of sight with distinct photometric redshifts. The remaining objects await more follow-up observations to confirm their nature. The lenses and the background sources have median redshifts z_L_=0.6 and z_S_=2.5, respectively, and are observed out to z_L_=1.2 and z_S_=4.2. We measure the number counts of candidate lensed galaxies at 500{mu}m and compare them with theoretical predictions, finding a good agreement for a maximum magnification of the background sources in the range 10-20. These values are consistent with the magnification factors derived from the lens modelling of individual systems. The catalogue presented here provides sub-mm bright targets for follow-up observations aimed at exploiting gravitational lensing, to study with unprecedented details the morphological and dynamical properties of dusty star-forming regions in z>=1.5 galaxies.
5920. H-ATLAS Catalog
- ID:
- ivo://irsa.ipac/Herschel/Catalog/H-ATLAS/H-ATLAS_Cat
- Title:
- H-ATLAS Catalog
- Short Name:
- H-ATLAS_Cat
- Date:
- 01 Oct 2018 20:27:20
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- The Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) is a survey of 600 deg^2 in five photometric bands - 100, 160, 250, 350 and 500 microns - with the Photoconductor Array Camera and Spectrometer (PACS) and Spectral and Photometric Imaging Receiver (SPIRE) cameras. H-ATLAS DR1 includes the survey of three fields on the celestial equator, covering a total area of 161.6 deg^2 and previously observed in the Galaxy and Mass Assembly (GAMA) spectroscopic survey. The data release main catalogue (HATLAS_DR1_CATALOGUE.FITS) contains only the 'best' candidate ID to each SPIRE source (where available). Most users will find in this catalogue everything they will need for their science purposes. A second catalogue is also available (HATLAS_DR1_CATALOGUE_ALLIDS.FITS), which contains all possible counterparts within the search radius of each SPIRE source, and provides the full LR statistics so that these may be independently analysed as the user wishes. To select only sources which have reliable optical IDs, a cut of Reliability#0.8 is recommended, although other cuts on Reliability or LR may be suitable for different purposes as discussed in Bourne et al. (2016).