- ID:
- ivo://CDS.VizieR/J/A+A/562/A56
- Title:
- Cyanomethyl anion and its deuterated derivatives
- Short Name:
- J/A+A/562/A56
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- It has long been suggested that CH_2_CN^-^ (cyanomethyl anion) might be a carrier of one of the many poorly characterized diffuse interstellar bands. In this paper, our aim is to study various forms (ionic, neutral, and deuterated isotopomer) of CH_2_CN (cyanomethyl radical) in the interstellar medium. The aim of this paper is to predict spectroscopic characteristics of various forms of CH_2_CN and its deuterated derivatives. Moreover, we would like to model the interstellar chemistry for predicting the column densities of such species around dark cloud conditions.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/724/994
- Title:
- Cyano- to methanol and ammonia observations
- Short Name:
- J/ApJ/724/994
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As part of an effort to study gas-grain chemical models in star-forming regions as they relate to molecules containing cyanide (-C{\equiv}N) groups, we present here a search for the molecules 2-cyanoethanol (OHCH_2_CH_2_CN) and methoxyacetonitrile (CH_3_OCH_2_CN) in the galactic center region SgrB2. These species are structural isomers of each other and are targeted to investigate the cross-coupling of pathways emanating from the photolysis products of methanol and ammonia with pathways involving cyano-containing molecules. Methanol and ammonia ices are two of the main repositories of the elements C, O, and N in cold clouds and understanding their link to cyanide chemistry could give important insights into prebiotic molecular evolution. Neither species was positively detected, but the upper limits we determined allow comparison to the general patterns gleaned from chemical models. Our results indicate the need for an expansion of the model networks to better deal with cyano-chemistry, in particular with respect to pathways including products of methanol photolysis. In addition to these results, the two main observational routes for detecting new interstellar molecules are discussed.
- ID:
- ivo://CDS.VizieR/J/other/JAD/26.1
- Title:
- CY Aqr CCD photometry 2019-2020 seasons
- Short Name:
- J/other/JAD/26.1
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Based on 28 partial nights of CCD monitoring, we derive 49 new times of maximum light of the SX Phoenicis star CY Aquarii. These times extend the linear ephemeris for a time interval covering the last eight years.
- ID:
- ivo://CDS.VizieR/J/other/JAD/24.4
- Title:
- CY Aqr CCD photometry 2016-2017-2018 seasons
- Short Name:
- J/other/JAD/24.4
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Based on more than 37 partial nights of CCD monitoring, we derive 64 new times of maximum light of the SX Phoenicis star CY Aquarii. These times support a linear ephemeris for the time interval 2013-2018.
- ID:
- ivo://CDS.VizieR/J/other/JAD/17.2
- Title:
- CY Aqr differential light curves
- Short Name:
- J/other/JAD/17.2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 24 new times of maximum of the SX Phoenicis star CY Aquarii. These times lead to a slightly more precise local linear ephemeris for 2003-2010.
- ID:
- ivo://CDS.VizieR/J/other/JAD/18.2
- Title:
- CY Aqr multiband photometry: 2011 season
- Short Name:
- J/other/JAD/18.2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on more than a dozen partial nights of filterless CCD photometry combined with Stromgren uvby photomultiplier photometry, we derive 29 new times of maximum light of the SX Phoenicis star CY Aquarii. These times support a linear ephemeris for 2003-2011. In addition, we present uvby light curves for this star. Our dataset displays the smallest residual spread compared to any other substantial dataset published during the last decade.
- ID:
- ivo://CDS.VizieR/J/AJ/107/1868
- Title:
- Cyclic period variability in SW Cyg
- Short Name:
- J/AJ/107/1868
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Timings of primary eclipse up through 1992 are collected, plus a few overlooked in earlier studies. Analysis shows that, after decreasing until ~1919 and increasing since then, the period has now started decreasing again, with the inflection point of the O-C curve being ~1972. The shortest period was 4.5727 days, the longest 4.5732 days, with a full cycle length of 96 yr. Explanation by the time-delay effect, due to orbital motion around a third body, would require an unseen black hole companion of >=10M_{sun}_. A magnetic cycle operating in the K-type subgiant, an active dynamo star because of its convection and rapid rotation, is the best explanation.
- ID:
- ivo://CDS.VizieR/J/A+A/395/129
- Title:
- Cyclotron lines in Vela X-1
- Short Name:
- J/A+A/395/129
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Fitting parameters for the phase resolved spectra of the 2000 and 1998 observation are given. The model in use is the Negative Positive EXponential (NPEX) model (with Gamma_2_ always fixed to -2, Mihara, 1995, Ph.D. Thesis, Riken, Tokyo) modified by photoelectric absorption, an additive iron line at ~6.4keV, and none, one, or two cyclotron resonant scattering features (CRSF)s at ~25 and ~50keV. The phase bins for the 2000 observation are: - rise, center, and fall of the main pulse - rise part 1, rise part 2, center, and fall of the secondary pulse - the two inter pulse phases The phase bins for the 1998 observation are: - rise and fall of the main pulse - rise and fall of the secondary pulse - the two inter pulse phases
- ID:
- ivo://CDS.VizieR/J/A+A/608/A103
- Title:
- 43 Cyg decorrelated 156-day light curve
- Short Name:
- J/A+A/608/A103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometric time series of the gamma Doradus star 43 Cyg obtained with the BRITE-Constellation nano-satellites allow us to study its pulsational properties in detail and to constrain its interior structure. We aim to find a g-mode period spacing pattern that allows us to determine the near-core rotation rate of 43 Cyg and redetermine the star's fundamental atmospheric parameters and chemical composition. We conducted a frequency analysis using the 156-days long data set obtained with the BRITE-Toronto satellite and employed a suite of MESA/GYRE models to derive the mode identification, asymptotic period spacing and near-core rotation rate. We also used high-resolution, high signal-to-noise ratio spectroscopic data obtained at the 1.2m Mercator telescope with the HERMES spectrograph to redetermine the fundamental atmospheric parameters and chemical composition of 43 Cyg using the software Spectroscopy Made Easy (SME). We detected 43 intrinsic pulsation frequencies and identified 18 of them to be part of a period spacing pattern consisting of prograde dipole modes with an asymptotic period spacing of 2970(+700,-570)s. The near-core rotation rate was determined to be 0.56(+0.12,-0.14)c/d. The atmosphere of 43 Cyg shows solar chemical composition at an effective temperature of 7150+/-150K, a logg of 4.2+/-0.6dex and a projected rotational velocity, vsini, of 44+/-4km/s. The morphology of the observed period spacing patterns shows indications of the presence of a significant chemical gradient in the stellar interior.
- ID:
- ivo://CDS.VizieR/J/A+A/610/A70
- Title:
- 28 Cygni BRITE and SMEI satellite photometry
- Short Name:
- J/A+A/610/A70
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The BRITE Constellation of nanosatellites obtained mmag photometry of 28 Cygni for 11 months in 2014-2016. Observations with the Solar Mass Ejection Imager in 2003-2010 and 118 H{alpha} line profiles were added. For decades, 28 Cyg has exhibited four large-amplitude frequencies: two closely spaced frequencies of spectroscopically confirmed g modes near 1.5c/d, one slightly lower exophotospheric (Stefl) frequency, and at 0.05c/d the difference frequency between the two g modes. This top-level framework is indistinguishable from eta Cen (Paper I), which is also very similar in spectral type, rotation rate, and viewing angle. The Stefl frequency is the only one that does not seem to be affected by the difference frequency. The amplitude of the latter undergoes large variations; around maximum the amount of near-circumstellar matter is increased, and the amplitude of the Stefl frequency grows by some factor. During such brightenings dozens of transient spikes appear in the frequency spectrum, concentrated in three groups. Only eleven frequencies were common to all years of BRITE observations. Be stars seem to be controlled by several coupled clocks, most of which are not very regular on timescales of weeks to months but function for decades. The combination of g modes to the low difference frequency and/or the atmospheric response to it appears significantly nonlinear. Like in eta Cen, the difference-frequency variability seems the main responsible for the modulation of the star-to-disc mass transfer in 28 Cyg. A hierarchical set of difference frequencies may reach the longest timescales known of the Be phenomenon.