- ID:
- ivo://CDS.VizieR/J/AJ/128/463
- Title:
- A preliminary 20pc census from the NLTT catalogue
- Short Name:
- J/AJ/128/463
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Continuing our census of late-type dwarfs in the solar neighborhood, we present BVRI photometry and optical spectroscopy of 800 mid-type M dwarfs drawn from the NLTT proper-motion catalog. The targets are taken both from our own cross-referencing of the NLTT Catalogue and the 2MASS Second Incremental Data Release, and from the revised NLTT compiled recently by Salim & Gould (Cat. <J/ApJ/582/1011>). All are identified as nearby-star candidates based on their location in the (m_r_, m_r_-K_s_) diagram. Three hundred stars discussed here have previous astrometric, photometric, or spectroscopic observations. We present new BVRI photometry for 101 stars, together with low-resolution spectroscopy of a further 400 dwarfs.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/460/650
- Title:
- Apsidal motions of 90 SMC eccentric binaries
- Short Name:
- J/MNRAS/460/650
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examined light curves of 1138 stars brighter than 18.0mag in the I band and less than a mean magnitude error of 0.1mag in the V band from the Optical Gravitational Lensing Experiment (OGLE)-III eclipsing binary catalogue, and found 90 new binary systems exhibiting apsidal motion. In this study, the samples of apsidal motion stars in the Small Magellanic Cloud (SMC) were increased by a factor of about 3.0 than previously known. In order to determine the period of the apsidal motion for the binaries, we analysed in detail both the light curves and eclipse timings using the MACHO (MAssive Compact Halo Objects) and OGLE photometric data base. For the eclipse timing diagrams of the systems, new times of minimum light were derived from the full light curve combined at intervals of one year from the survey data. The new 90 binaries have apsidal motion periods in the range of 12-897yr. An additional short-term oscillation was detected in four systems (OGLE-SMC-ECL-1634, 1947, 3035, and 4946), which most likely arises from the existence of a third body orbiting each eclipsing binary. Since the systems presented here are based on homogeneous data and have been analysed in the same way, they are suitable for further statistical analysis.
- ID:
- ivo://CDS.VizieR/J/AJ/140/1475
- Title:
- ARAUCARIA: NGC 7793 Cepheids
- Short Name:
- J/AJ/140/1475
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For the first time, we have detected Cepheid variables in the Sculptor Group spiral galaxy NGC 7793. From wide-field images obtained in the optical V and I bands on 56 nights in 2003-2005, we have discovered 17 long-period (24-62 days) Cepheids whose periods and mean magnitudes define tight period-luminosity relations. We use the (V-I) Wesenheit index to determine a reddening-free true distance modulus to NGC 7793 of 27.68+/-0.05mag (internal error) +/-0.08mag (systematic error).
- ID:
- ivo://CDS.VizieR/J/AJ/132/2556
- Title:
- ARAUCARIA project: Cepheids in NGC 55
- Short Name:
- J/AJ/132/2556
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have detected, for the first time, Cepheid variables in the Sculptor Group SB(s)m galaxy NGC 55. From wide-field images obtained in the optical V and I bands during 77 nights in 2002-2003, we have found 143 Cepheids with periods ranging from 5.6 to 175.9 days; 133 of these objects have periods longer than 10 days, making NGC 55 to date the galaxy with the largest known number of long-period Cepheids in the Sculptor Group.
- ID:
- ivo://CDS.VizieR/J/AJ/134/594
- Title:
- Araucaria project: Cepheids in WLM galaxy
- Short Name:
- J/AJ/134/594
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have conducted an extensive wide-field imaging survey for Cepheid variables in the Local Group irregular galaxy WLM. From data obtained on 101 nights, we have discovered 60 Cepheids, which include 14 of the 15 Cepheid variables previously detected by Sandage and Carlson. Our Cepheid survey in WLM should be practically complete down to a period of 3-days. Importantly, we have found for the first time a long-period Cepheid (P=54.2-days) in this galaxy, alleviating the problem that WLM with its many blue, massive stars does not contain Cepheids with periods longer than about 10-days.
- ID:
- ivo://CDS.VizieR/J/AJ/123/789
- Title:
- ARAUCARIA project: NGC 300 Cepheid variables
- Short Name:
- J/AJ/123/789
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have conducted a survey for Cepheid variables in the Sculptor group spiral NGC 300. Based on observations obtained with the Wide-Field Camera at the 2.2m ESO/MPI telescope at the La Silla observatory in Chile during 29 nights spread over a 5.3 month interval. The telescope was equipped with the ESO mosaic Wide-Field Camera (WFI) consisting of eight 2048x4098 pixel arrays. The CCDs were separated by gaps of 23.8" and 14.3" in right ascension and declination, respectively. The total field of view was about 34'x33' with a scale of 0.238"/pixel. 117 Cepheids and 12 Cepheid candidates were found, which cover the period range from 115 to 5.4 days. We present a catalog that provides equatorial coordinates, period, time of maximum brightness, and intensity mean B and V magnitudes for each variable, and we show phased B and V light curves for all the Cepheids found. We also present the individual B and V observations for each Cepheid in our catalog. During our search we rediscovered all 18 previously known Cepheids and confirmed the Cepheid nature of three Cepheid candidates from the previous photographic survey of Graham (1984AJ.....89.1332G). Star V4 in Graham's list (1984AJ.....89.1332G), classified by him as an eclipsing binary, turns out to be another Cepheid. We find very good agreement between our photometry and that obtained by Freedman et al. (1992ApJ...396...80F) from ground-based CCD data for common stars. Using the earlier data together with our new data, we were able to significantly improve the periods for 15 Cepheids in our sample.
- ID:
- ivo://CDS.VizieR/J/AJ/128/2815
- Title:
- ARAUCARIA project: NGC 6822 Cepheid variables
- Short Name:
- J/AJ/128/2815
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained mosaic images of NGC 6822 in the V and I bands on 77 nights. From these data, we have conducted an extensive search for Cepheid variables over the entire field of the galaxy, and we have found 116 such variables with periods ranging from 1.7 to 124 days. We used the long-period (>5.6 days) Cepheids to establish the period-luminosity (PL) relations in V, I, and in the reddening-independent Wesenheit index, which are all very tightly defined.
- ID:
- ivo://CDS.VizieR/J/AJ/128/1167
- Title:
- ARAUCARIA project : NGC 300 Cepheid Variables. II
- Short Name:
- J/AJ/128/1167
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present VI data, derive improved periods and mean magnitudes for the variables, and construct period-luminosity relations in the V, I, and the reddening-independent V-I Wesenheit bands using 58 Cepheid variables with periods between 11 and 90 days.
- ID:
- ivo://CDS.VizieR/J/ApJ/871/129
- Title:
- A redshift catalog of the galaxy cluster A2029
- Short Name:
- J/ApJ/871/129
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We explore the structure of galaxy cluster A2029 and its surroundings based on intensive spectroscopy along with X-ray and weak lensing observations. The redshift survey includes 4376 galaxies (1215 spectroscopic cluster members) within 40' of the cluster center; the redshifts are included here. Two subsystems, A2033 and a southern infalling group (SIG), appear in the infall region based on the spectroscopy, as well as on the weak lensing and X-ray maps. The complete redshift survey of A2029 also identifies at least 12 foreground and background systems (10 are extended X-ray sources) in the A2029 field; we include a census of their properties. The X-ray luminosities (L_X_)-velocity dispersions ({sigma}_cl_) scaling relations for A2029, A2033, SIG, and the foreground/background systems are consistent with the known cluster scaling relations. The combined spectroscopy, weak lensing, and X-ray observations provide a robust measure of the masses of A2029, A2033, and SIG. The total mass of the infalling groups (A2033 and SIG) is ~60% of the M200 of the primary cluster, A2029. Simple dynamical considerations suggest that A2029 will accrete these subsystems in the next few Gyr. In agreement with simulations and other clusters observed in a similar redshift range, the total mass in the A2029 infall region is comparable to the A2029 M200 and will mostly be accreted in the long-term future.
- ID:
- ivo://CDS.VizieR/J/ApJ/842/88
- Title:
- A redshift survey of the central region of A2199
- Short Name:
- J/ApJ/842/88
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results from an extensive spectroscopic survey of the central region of the nearby galaxy cluster Abell 2199 (A2199) at z=0.03. By combining 775 new redshifts from the MMT/Hectospec observations with the data in the literature, we construct a large sample of 1624 galaxies with measured redshifts at R<30', which results in high spectroscopic completeness at r_petro,0_<20.5 (77%). We use these data to study the kinematics and clustering of galaxies, focusing on the comparison with those of the intracluster medium (ICM) from Suzaku X-ray observations. We identify 406 member galaxies of A2199 at R<30' using the caustic technique. The velocity dispersion profile of cluster members appears smoothly connected to the stellar velocity dispersion profile of the cD galaxy. The luminosity function is well fitted with a Schechter function at M_r_< -15. The radial velocities of cluster galaxies generally agree well with those of the ICM, but there are some regions where the velocity difference between the two is about a few hundred kilometers per second. The cluster galaxies show a hint of global rotation at R<5' with v_rot_=300-600km/s, but the ICM in the same region does not show such rotation. We apply a friends-of-friends algorithm to the cluster galaxy sample at R<60' and identify 32 group candidates, and examine the spatial correlation between the galaxy groups and X-ray emission. This extensive survey in the central region of A2199 provides an important basis for future studies of interplay among the galaxies, the ICM, and the dark matter in the cluster.
