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2381. Solar Lyman irradiance line profiles
ID:
ivo://CDS.VizieR/J/A+A/581/A26
Title:
Solar Lyman irradiance line profiles
Short Name:
J/A+A/581/A26
Date:
21 Oct 2021
Publisher:
CDS
Description:
Accurate hydrogen spectra emitted by the entire solar disc in the Ly-{alpha} and Ly-{beta} lines are valuable for deriving the distribution and the behaviour of atomic hydrogen in the heliosphere, for understanding the UV emissions of solar type stars better, and finally for estimating the solar energy input that mainly initiates the chemical processes occurring in the planetary and cometary outer atmospheres. In this paper we want to accurately determine the irradiance solar spectral profiles of Ly-{alpha} and Ly-{beta} and their evolution through the solar activity cycle 23. The SUMER/SOHO spectrometer is a slit spectrometer that is only able to analyse a small part of the solar image. Consequently, we used the scattered light properties of the telescope to obtain average spectra over the solar disc. Then the profile is calibrated using the SOLSTICE/UARS and TIMED/SEE irradiance spectra.
2382. SOLAR/SOLSPEC Spectral Irradiance - 0.5-3000nm
ID:
ivo://CDS.VizieR/J/A+A/611/A1
Title:
SOLAR/SOLSPEC Spectral Irradiance - 0.5-3000nm
Short Name:
J/A+A/611/A1
Date:
21 Oct 2021
Publisher:
CDS
Description:
Since April 5, 2008 and up to February 15, 2017, the SOLar SPECtrometer (SOLSPEC) instrument of the SOLAR payload on board the International Space Station (ISS) has performed accurate measurements of solar spectral irradiance (SSI) from the middle ultraviolet to the infrared (165 to 3088nm). These measurements are of primary importance for a better understanding of solar physics and the impact of solar variability on climate. In particular, a new reference solar spectrum (SOLAR-ISS) is established in April 2008 during the solar minima of cycles 23-24 thanks to revised engineering corrections, improved calibrations, and advanced procedures to account for thermal and aging corrections of the SOLAR/SOLSPEC instrument. The main objective of this article is to present a new high-resolution solar spectrum with a mean absolute uncertainty of 1.26% at 1{sigma} from 165 to 3000nm. This solar spectrum is based on solar observations of the SOLAR/SOLSPEC space-based instrument. The SOLAR/SOLSPEC instrument consists of three separate double monochromators that use concave holographic gratings to cover the middle ultraviolet (UV), visible (VIS), and infrared (IR) domains. Our best ultraviolet, visible, and infrared spectra are merged into a single absolute solar spectrum covering the 165-3000nm domain. The resulting solar spectrum has a spectral resolution varying between 0.6 and 9.5nm in the 165-3000nm wavelength range. We build a new solar reference spectrum (SOLAR-ISS) by constraining existing high-resolution spectra to SOLAR/SOLSPEC observed spectrum. For that purpose, we account for the difference of resolution between the two spectra using the SOLAR/SOLSPEC instrumental slit functions. Using SOLAR/SOLSPEC data, a new solar spectrum covering the 165-3000nm wavelength range is built and is representative of the 2008 solar minimum. It has a resolution better than 0.1nm below 1000nm and 1nm in the 1000-3000nm wavelength range. The new solar spectrum (SOLAR-ISS) highlights significant differences with previous solar reference spectra and with solar spectra based on models. The integral of the SOLAR-ISS solar spectrum yields a total solar irradiance of 1372.3+/-16.9W/m^2^ at 1{sigma}, that is yet 11W/m^2^ over the value recommended by the International Astronomical Union in 2015.
2383. SOLAR/SOLSPEC UV SSI from 2008-2015
ID:
ivo://CDS.VizieR/J/other/SoPh/291.3527
Title:
SOLAR/SOLSPEC UV SSI from 2008-2015
Short Name:
J/other/SoPh/291
Date:
21 Oct 2021
Publisher:
CDS
Description:
Accurate measurements of the solar spectral irradiance (SSI) and its temporal variations are of primary interest to better understand solar mechanisms, and the links between solar variability and Earth's atmosphere and climate. The SOLar SPECtrum (SOLSPEC) instrument of the Solar Monitoring Observatory (SOLAR) payload onboard the International Space Station (ISS) has been built to carry out SSI measurements from 165 to 3088nm. We focus here on the ultraviolet (UV) part of the measured solar spectrum (wavelengths less than 400 nm) because the UV part is potentially important for understanding the solar forcing of Earth's atmosphere and climate. We present here SOLAR/SOLSPEC UV data obtained since 2008, and their variations in three spectral bands during Solar Cycle 24. They are compared with previously reported UV measurements and model reconstructions, and differences are discussed.
2384. Solar spectral irradiance
ID:
ivo://CDS.VizieR/J/ApJ/789/117
Title:
Solar spectral irradiance
Short Name:
J/ApJ/789/117
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use solar spectra obtained by the Ozone Monitoring Instrument (OMI) on board the Aura satellite to detect and follow long-term (years) and short-term (weeks) changes in the solar spectral irradiance (SSI) in the 265-500 nm spectral range. During solar Cycle 24, in the relatively line-free regions the SSI changed by ~0.6%+/-0.2% around 265 nm. These changes gradually diminish to 0.15%+/-0.20% at 500 nm. All strong spectral lines and blends, with the notable exception of the upper Balmer lines, vary in unison with the solar "continuum." Besides the lines with strong chromospheric components, the most involved species include Fe I blends and all prominent CH, NH, and CN spectral bands. Following the general trend seen in the solar "continuum," the variability of spectral lines also decreases toward longer wavelengths. The long-term solar cycle SSI changes are closely, to within the quoted 0.1%-0.2% uncertainties, matched by the appropriately adjusted short-term SSI variations derived from the 27 day rotational modulation cycles. This further strengthens and broadens the prevailing notion about the general scalability of the UV SSI variability to the emissivity changes in the Mg II 280 nm doublet on timescales from weeks to years. We also detect subtle deviations from this general rule: the prominent spectral lines and blends at {lambda} >~ 350 nm show slightly more pronounced 27 day SSI changes when compared to the long-term (years) trends. We merge the solar data from Cycle 21 with the current Cycle 24 OMI and GOME-2 observations and provide normalized SSI variations for the 170-795 nm spectral region.
2385. Solar spectral irradiance during Solar Cycle 24
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.
2386. SONYC census of very low-mass objects in NGC1333
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.
2387. SONYC new brown dwarfs in {rho} Oph
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.
2388. SOPHIE data of Gliese 411
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.
2389. Southern MK Standards 5800-10200A
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.
2390. SOVAP-PICARD total solar irradiance
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.

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