- ID:
- ivo://CDS.VizieR/J/A+A/645/A2
- Title:
- Solar spectral irradiance during Solar Cycle 24
- Short Name:
- J/A+A/645/A2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Solar spectral irradiance (SSI) is the wavelength-dependent energy input to the top of the Earth's atmosphere. Solar ultraviolet (UV) irradiance represents the primary forcing mechanism for the photochemistry, heating, and dynamics of the Earth's atmosphere. Hence, both temporal and spectral variations in solar UV irradiance represent crucial inputs to the modeling and understanding of the behavior of the Earth's atmosphere. Therefore, measuring the long-term solar UV irradiance variations over the 11-year solar activity cycle (and over longer timescales) is fundamental. Thus, each new solar spectral irradiance dataset based on long-term observations represents a major interest and can be used for further investigations of the long-term trend of solar activity and the construction of a homogeneous solar spectral irradiance record. The main objective of this article is to present a new solar spectral irradiance database (SOLAR-v) with the associated uncertainties. This dataset is based on solar UV irradiance observations (165-300nm) of the SOLAR/SOLSPEC space-based instrument, which provides measurements of the full-disk SSI during solar cycle 24. SOLAR/SOLSPEC made solar acquisitions between April 5, 2008 and February 10, 2017. During this period, the instrument was affected by the harsh space environment that introduces instrumental trends (degradation) in the SSI measurements. A new method based on an adaptation of the Multiple Same-Irradiance-Level (MuSIL) technique was used to separate solar variability and any uncorrected instrumental trends in the SOLAR/SOLSPEC UV irradiance measurements. A new method for correcting degradation has been applied to the SOLAR/SOLSPEC UV irradiance records to provide new solar cycle variability results during solar cycle 24. Irradiances are reported at a mean solar distance of 1 astronomical unit (AU). In the 165-242nm spectral region, the SOLAR/SOLSPEC data agrees with the observations (SORCE/SOLSTICE) and models (SATIRE-S, NRLSSI 2) to within the 1-sigma error envelope. Between 242 and 300nm, SOLAR/SOLSPEC agrees only with the models.
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- ID:
- ivo://CDS.VizieR/J/ApJ/744/6
- Title:
- SONYC census of very low-mass objects in NGC1333
- Short Name:
- J/ApJ/744/6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- SONYC - Substellar Objects in Nearby Young Clusters - is a program to investigate the frequency and properties of young substellar objects with masses down to a few times that of Jupiter. In a series of papers we have obtained follow-up spectroscopy for a large number of candidate very low mass (VLM) members of the ~1Myr old cluster NGC1333 in the Perseus star forming region. For more details on the survey, see the associated paper (Scholz et al., 2012ApJ...744....6S). Here we present a census of spectroscopically confirmed very low mass objects in NGC1333. We include all objects with spectral type of M5 or later and/or effective temperature of 3200K or cooler. In total, there are now 58 objects which fulfill these criteria. In three tables we list photometric and spectroscopic properties for our own sample as well as for objects listed in the literature. In addition, we also include three tables of the objects that have been rejected as very low mass cluster members based on our spectroscopic follow-up. Finally, we attach the two photometric candidate lists from which the spectroscopic sample was extracted, see Scholz et al. (2012ApJ...756...24S) for more details on these catalogues.
- ID:
- ivo://CDS.VizieR/J/ApJ/744/134
- Title:
- SONYC new brown dwarfs in {rho} Oph
- Short Name:
- J/ApJ/744/134
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- SONYC - Substellar Objects in Nearby Young Clusters - is a survey program to investigate the frequency and properties of substellar objects with masses down to a few times that of Jupiter in nearby star-forming regions. In two papers of the SONYC series we have obtained follow-up spectroscopy for a large number of candidate very low ma ss (VLM) members of the ~1Myr old cluster rho Ophiuchi. For more details on the survey, see the associated paper (Muzic et al., 2012ApJ...744..134M). Here we publish the two catalogues of photometric candidate members from which the spectroscopic samples were extracted (see Geers et al. 2011ApJ...726...23G and Muzic et al. 2012ApJ...744..134M for more details on these catalogues). We include a table containing all the spectroscopically confirmed VLM members of the cluster observed within the SONYC campaign. We also attach and a table with all the objects that have been rejected as VLM members based on our spectroscopic follow-up. The majority of these latter objects are expected to be background contaminants, although some of them could also be embedded cluster members with spectral types earlier than M.
- ID:
- ivo://CDS.VizieR/J/A+A/625/A17
- Title:
- SOPHIE data of Gliese 411
- Short Name:
- J/A+A/625/A17
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Periodic radial velocity variations in the nearby M-dwarf star Gl 411 are reported, based on measurements with the SOPHIE spectrograph. Current data do not allow us to distinguish between a 12.95-day period and its one-day alias at 1.08-days, but favour the former slightly. The velocity variation has an amplitude of 1.6m/s, making this the lowest-amplitude signal detected with SOPHIE up to now. We have performed a detailed analysis of the significance of the signal and its origin, including extensive simulations with both uncorrelated and correlated noise, representing the signal induced by stellar activity. The signal is significantly detected, and the results from all tests point to its planetary origin. Additionally, the presence of an additional acceleration in the velocity time series is suggested by the current data. On the other hand, a previously reported signal with a period of 9.9 days, detected in HIRES velocities of this star, is not recovered in the SOPHIE data. An independent analysis of the HIRES dataset also fails to unveil the 9.9-day signal. If the 12.95-day period is the real one, the amplitude of the signal detected with SOPHIE implies the presence of a planet, called Gl 411 b, with a minimum mass of around three Earth masses, orbiting its star at a distance of 0.079AU. The planet receives about 3.5 times the insolation received by Earth, which implies an equilibrium temperature between 256 and 350K, and makes it too hot to be in the habitable zone. At a distance of only 2.5pc, Gl 411 b, is the third closest low-mass planet detected to date. Its proximity to Earth will permit probing its atmosphere with a combination of high-contrast imaging and high-dispersion spectroscopy in the next decade.
- ID:
- ivo://CDS.VizieR/III/179
- Title:
- Southern MK Standards 5800-10200A
- Short Name:
- III/179
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spectra are presented for MK standards in the wavelength range 580-1020nm. The stars cover the normal spectral types O to M and luminosity types I, III, and V. In addition, a small number of peculiar stars are included. The data are in 137 FITS files, in the "fits" subdirectory. The list of the 137 stars is included in the "stars.dat" file; note that the list is not identical to the stars listed in Table1 of the paper.
- ID:
- ivo://CDS.VizieR/VI/152
- Title:
- SOVAP-PICARD total solar irradiance
- Short Name:
- VI/152
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- From the SOlar VAriability PICARD (SOVAP) space-based radiometer, we obtained a new time series of the total solar irradiance (TSI) during Solar Cycle 24. Based on SOVAP data, we obtained that the TSI input at the top of the Earth's atmosphere at a distance of one astronomical unit from the Sun is 1361.8+/-2.4W/m^2^ (1{sigma}) representative of the 2008 solar minimum period. From 2010 to 2014, the amplitude of the changes has been of the order of +/-0.1%, corresponding to a range of about 2.7W/m^2^. To determine the TSI from SOVAP, we present here an improved instrument equation. A parameter was integrated from a theoretical analysis that highlighted the thermo-electrical non-equivalence of the radiometric cavity. From this approach, we obtained values that are lower than those previously provided with the same type of instrument. The results in this paper supersede the previous SOVAP analysis and provide the best SOVAP-based TSI-value estimate and its temporal variation.
- ID:
- ivo://CDS.VizieR/J/ApJ/806/128
- Title:
- Space telescope RM project. I. NGC5548
- Short Name:
- J/ApJ/806/128
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the first results from a six-month long reverberation-mapping experiment in the ultraviolet based on 171 observations of the Seyfert 1 galaxy NGC 5548 with the Cosmic Origins Spectrograph on the Hubble Space Telescope. Significant correlated variability is found in the continuum and broad emission lines, with amplitudes ranging from ~30% to a factor of two in the emission lines and a factor of three in the continuum. The variations of all the strong emission lines lag behind those of the continuum, with HeII{lambda}1640 lagging behind the continuum by ~2.5 days and Ly{alpha}{lambda}1215, CIV{lambda}1550, and SiIV{lambda}1400 lagging by ~5-6 days. The relationship between the continuum and emission lines is complex. In particular, during the second half of the campaign, all emission-line lags increased by a factor of 1.3-2 and differences appear in the detailed structure of the continuum and emission-line light curves. Velocity-resolved cross-correlation analysis shows coherent structure in lag versus line of sight velocity for the emission lines; the high-velocity wings of CIV respond to continuum variations more rapidly than the line core, probably indicating higher velocity broad-line region clouds at smaller distances from the central engine. The velocity-dependent response of Ly{alpha}, however, is more complex and will require further analysis.
- ID:
- ivo://CDS.VizieR/J/ApJ/881/153
- Title:
- Space telescope RM project. VIII. NGC5548 HST sp.
- Short Name:
- J/ApJ/881/153
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We model the ultraviolet spectra of the Seyfert 1 galaxy NGC 5548 obtained with the Hubble Space Telescope during the 6 month reverberation mapping campaign in 2014. Our model of the emission from NGC 5548 corrects for overlying absorption and deblends the individual emission lines. Using the modeled spectra, we measure the response to continuum variations for the deblended and absorption-corrected individual broad emission lines, the velocity-dependent profiles of Ly{alpha} and CIV, and the narrow and broad intrinsic absorption features. We find that the time lags for the corrected emission lines are comparable to those for the original data. The velocity-binned lag profiles of Ly{alpha} and CIV have a double-peaked structure indicative of a truncated Keplerian disk. The narrow absorption lines show a delayed response to continuum variations corresponding to recombination in gas with a density of ~10^5^cm^-3^. The high-ionization narrow absorption lines decorrelate from continuum variations during the same period as the broad emission lines. Analyzing the response of these absorption lines during this period shows that the ionizing flux is diminished in strength relative to the far-ultraviolet continuum. The broad absorption lines associated with the X-ray obscurer decrease in strength during this same time interval. The appearance of X-ray obscuration in ~2012 corresponds with an increase in the luminosity of NGC 5548 following an extended low state. We suggest that the obscurer is a disk wind triggered by the brightening of NGC 5548 following the decrease in size of the broad-line region during the preceding low-luminosity state.
- ID:
- ivo://CDS.VizieR/J/ApJ/837/131
- Title:
- Space telescope RM project. V. NGC5548 sp. monitoring
- Short Name:
- J/ApJ/837/131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an optical spectroscopic monitoring program targeting NGC 5548 as part of a larger multiwavelength reverberation mapping campaign. The campaign spanned 6 months and achieved an almost daily cadence with observations from five ground-based telescopes. The H{beta} and HeII{lambda}4686 broad emission-line light curves lag that of the 5100{AA} optical continuum by 4.17_-0.36_^+0.36^days and 0.79_-0.34_^+0.35^days, respectively. The H{beta} lag relative to the 1158{AA} ultraviolet continuum light curve measured by the Hubble Space Telescope is ~50% longer than that measured against the optical continuum, and the lag difference is consistent with the observed lag between the optical and ultraviolet continua. This suggests that the characteristic radius of the broad-line region is ~50% larger than the value inferred from optical data alone. We also measured velocity-resolved emission-line lags for H{beta} and found a complex velocity-lag structure with shorter lags in the line wings, indicative of a broad-line region dominated by Keplerian motion. The responses of both the H{beta} and He II emission lines to the driving continuum changed significantly halfway through the campaign, a phenomenon also observed for CIV, Ly{alpha}, HeII(+OIII]), and SiIV(+OIV]) during the same monitoring period. Finally, given the optical luminosity of NGC5548 during our campaign, the measured H{beta} lag is a factor of five shorter than the expected value implied by the R_BLR_-L_AGN_ relation based on the past behavior of NGC 5548.
- ID:
- ivo://CDS.VizieR/J/ApJ/723/993
- Title:
- Spatial extent of (U)LIRGs in the MIR. I.
- Short Name:
- J/ApJ/723/993
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of the extended mid-infrared (MIR) emission of the Great Observatories All-Sky LIRG Survey sample based on 5-15um low-resolution spectra obtained with the Infrared Spectrograph on Spitzer. We calculate the fraction of extended emission (FEE) as a function of wavelength for the galaxies in the sample, FEE_{lambda}_, defined as the fraction of the emission which originates outside of the unresolved component of a source at a given distance. We find that the FEE_{lambda}_ varies from one galaxy to another, but we can identify three general types of FEE_{lambda}_: one where FEE_{lambda}_ is constant, one where features due to emission lines and polycyclic aromatic hydrocarbons appear more extended than the continuum, and a third which is characteristic of sources with deep silicate absorption at 9.7um. The mean size of the LIRG cores at 13.2um is 2.6kpc. However, once the IR luminosity of the systems reaches the threshold of L_IR_~10^11.8^L_{sun}_, slightly below the regime of Ultra-luminous Infrared Galaxies (ULIRGs), all sources become clearly more compact, with FEE_13.2um_<~0.2, and their cores are unresolved. Our estimated upper limit for the core size of ULIRGs is less than 1.5kpc.
