- ID:
- ivo://CDS.VizieR/J/A+A/574/A37
- Title:
- Movies of 2012-10-16 solar flare
- Short Name:
- J/A+A/574/A37
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We used multiwavelength high-resolution data from ARIES, THEMIS, and SDO instruments to analyze a non-standard, C3.3 class flare produced within the active region NOAA 11589 on 2012 October 16. Magnetic flux emergence and cancellation were continuously detected within the active region, the latter leading to the formation of two filaments. Our aim is to identify the origins of the flare taking the complex dynamics of its close surroundings into account. We analyzed the magnetic topology of the active region using a linear force-free field extrapolation to derive its 3D magnetic configuration and the location of quasi-separatrix layers (QSLs), which are preferred sites for flaring activity. Because the active region's magnetic field was nonlinear force-free, we completed a parametric study using different linear force-free field extrapolations to demonstrate the robustness of the derived QSLs.
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- ID:
- ivo://CDS.VizieR/J/A+A/628/A103
- Title:
- Mt Wilson sunspot magnetic field measurements
- Short Name:
- J/A+A/628/A103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Systematic observations of magnetic field strength and polarity in sunspots began at Mount Wilson Observatory (MWO), USA in early 1917. Except for a few brief interruptions, this historical dataset continues till present. Here file Figs3_5.txt contains data shown in Figures 3-5; files Fig6a.txt and Fig6b.txt contain data shown in Figure 6, and file Fig7.txt contain data for Figure 7.
- ID:
- ivo://CDS.VizieR/J/ApJS/211/20
- Title:
- NiI transition probability measurements
- Short Name:
- J/ApJS/211/20
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Atomic transition probability measurements for 371 NiI lines in the UV through near-IR are reported. Branching fractions from data recorded using a Fourier transform spectrometer and a new echelle spectrograph are combined with published radiative lifetimes to determine these transition probabilities. Generally good agreement is found in comparisons to previously reported NiI transition probability measurements. Use of the new echelle spectrograph, independent radiometric calibration methods, and independent data analysis routines enable a reduction of systematic errors and overall improvement in transition probability uncertainty over previous measurements. The new NiI data are applied to high-resolution visible and UV spectra of the Sun and metal-poor star HD 84937 to derive new, more accurate Ni abundances. Lines covering a wide range of wavelength and excitation potential are used to search for non-LTE effects.
- ID:
- ivo://CDS.VizieR/J/A+A/585/A143
- Title:
- NIR spectroscopy of the Sun and HD20010
- Short Name:
- J/A+A/585/A143
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Effective temperature, surface gravity, and metallicity are basic spectroscopic stellar parameters necessary to characterize a star or a planetary system. Reliable atmospheric parameters for FGK stars have been obtained mostly from methods that rely on high resolution and high signal-to-noise optical spectroscopy. The advent of a new generation of high resolution near-infrared (NIR) spectrographs opens the possibility of using classic spectroscopic methods with high resolution and high signal-to-noise in the NIR spectral window. We compile a new iron line list in the NIR from a solar spectrum to derive precise stellar atmospheric parameters, comparable to the ones already obtained from high resolution optical spectra. The spectral range covers 10000{AA} to 25000{AA}, which is equivalent to the Y,J,H, and K-bands. Our spectroscopic analysis is based on the iron excitation and ionization balance done in local thermodynamic equilibrium. We use a high resolution and high signal-to-noise ratio spectrum of the Sun from the Kitt Peak telescope as a starting point to compile the iron line list. The oscillator strengths (loggf) of the iron lines were calibrated for the Sun. The abundance analysis was done using the MOOG code after measuring equivalent widths of 357 solar iron lines.
- ID:
- ivo://CDS.VizieR/J/A+A/525/A74
- Title:
- 540-690nm Solar Atlas
- Short Name:
- J/A+A/525/A74
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Astronomical research dealing with accurate radial velocity measurements need reliable astronomical standards to calibrate the spectrographs and to assess possible systematics. Stellar radial velocity standards offer a reference at the level of a few hundred m/s and are not adequate for most present needs. We aim to show that sunlight reflected by asteroids is a fairly accessible way to record a high-resolution solar spectrum from the whole disk, which can therefore be used as a radial velocity standard and can improve the uncertainties of solar line positions.
- ID:
- ivo://CDS.VizieR/J/other/ApSS/353.347
- Title:
- 398-710nm Sun spectral atlases
- Short Name:
- J/other/ApSS/353
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work, we present digital and graphical atlases of spectra of both the solar disk-center and of the limb near the Solar poles using data taken at the UTS-IAP & RIAAM (the University of Tabriz Siderostat, telescope and spectrograph jointly developed with the Institut d'Astrophysique de Paris and Research Institute for Astronomy and Astrophysics of Maragha). High resolution and high signal-to-noise ratio (SNR) CCD-slit spectra of the sun for 2 different parts of the disk, namely for {mu}=1.0 (solar center) & for {mu}=0.3 (solar limb) are provided and discussed. While there are several spectral atlases of the solar disk-center, this is the first spectral atlas ever produced for the solar limb at this spectral range. The resolution of the spectra is about R~70000 ({Delta}{lambda}~0.09{AA})} with the signal-to-noise ratio (SNR) of 400-600. The full atlas covers the 3980 to 7100{AA} spectral regions and contains 44 pages with three partial spectra of the solar spectrum put on each page to make it compact. The difference spectrum of the normalized each page to make it compact. The difference spectrum of the normalized solar disk-center and the solar limb is also included in the graphic presentation of the atlas to show the difference of line profiles, including far wings. The identification of most of the significant solar lines are included in the graphic presentation of the atlas. Telluric lines are producing a definite signature on the difference spectra which is easy to notice.
- ID:
- ivo://CDS.VizieR/J/A+A/576/A89
- Title:
- O abundances from HARPS in F-G stars
- Short Name:
- J/A+A/576/A89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a detailed and uniform study of oxygen abundance from two different oxygen lines at 6158{AA} and 6300{AA} in a large sample of solar-type stars. The results are used to check the behaviour of these spectral lines as oxygen abundance indicators and to study the evolution of oxygen in thick and thin disk populations of the Galaxy. Equivalent width measurements were carried out for the [OI]6158 and [OI]6300 lines. LTE abundances were obtained from these two lines in 610 and 535 stars, respectively. Careful error analysis has been performed.
- ID:
- ivo://CDS.VizieR/J/ApJ/710/1111
- Title:
- Observations of interplanetary shocks
- Short Name:
- J/ApJ/710/1111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the radio-emission characteristics of 222 interplanetary (IP) shocks detected by spacecraft at Sun-Earth L1 during solar cycle 23 (1996 to 2006, inclusive). A surprisingly large fraction of the IP shocks (~34%) was radio quiet (RQ; i.e., the shocks lacked type II radio bursts). We examined the properties of coronal mass ejections (CMEs) and soft X-ray flares associated with such RQ shocks and compared them with those of the radio-loud (RL) shocks. The CMEs associated with the RQ shocks were generally slow (average speed ~535km/s) and only ~40% of the CMEs were halos. The corresponding numbers for CMEs associated with RL shocks were 1237km/s and 72%, respectively. Thus, the CME kinetic energy seems to be the deciding factor in the radio-emission properties of shocks.
- ID:
- ivo://CDS.VizieR/J/A+AS/113/131
- Title:
- Observations of the Sun during 1994
- Short Name:
- J/A+AS/113/131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A program of solar observations at 30deg and 60deg zenith distance is in progress since 1990 with the modified Danjon astrolabe of Santiago. Results in right ascension, parameter Y and apparent semi-diameter of the Sun obtained with the astrolabe at both zenith distances during 1994, are available.
- ID:
- ivo://CDS.VizieR/J/A+AS/106/327
- Title:
- Observations of the Sun during 1993 at Santiago
- Short Name:
- J/A+AS/106/327
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
