Publications using ARAS ES spectra in 2023

Francois Teyssier · Post by **Francois Teyssier** » Tue Feb 06, 2024 9:46 am

Here's a list of papers using ARAS Eruptive Stars database in 2023.

1
Revisiting the classics: on the evolutionary origin of the 'Fe II' and 'He/N' spectral classes of novae
Aydi, E., Chomiuk, L., Strader, J., Sokolovsky, K. V., Williams, R. E., Buckley, D. A. H., & al. (18)
Monthly Notices of the Royal Astronomical Society, 527 2024/01/1
https://ui.adsabs.harvard.edu/abs/2024MNRAS.527.9303A
The optical spectra of novae are characterized by emission lines from the hydrogen Balmer series and either Fe II or He/N, leading to their traditional classification into two spectral classes: 'Fe II' and 'He/N'. For decades, the origins of these spectral features were discussed in the literature in the contexts of different bodies of gas or changes in the opacity of the ejecta, particularly associated with studies by R. E. Williams and S. N. Shore. Here, we revisit these major studies with dedicated, modern data sets, covering the evolution of several novae from early rise to peak all the way to the nebular phase. Our data confirm previous suggestions in the literature that the 'Fe II' and 'He/N' spectral classes are phases in the spectroscopic evolution of novae driven primarily by changes in the opacity, ionization, and density of the ejecta, and most if not all novae go through at least three spectroscopic phases as their eruptions evolve: an early He/N (phase 1; observed during the early rise to visible peak and characterized by P Cygni lines of He I and N II/III), then an Fe II (phase 2; observed near visible peak and characterized by P Cygni lines of Fe II and O I), and then a later He/N (phase 3; observed during the decline and characterized by emission lines of He I/II, N II/III), before entering the nebular phase. This spectral evolution seems to be ubiquitous across novae, regardless of their speed class; however the duration of each of these phases differs based on the speed class of the nova.

2
Study of the fastest classical nova, V1674 Her: photoionization and morpho-kinemetic model analysis
Habtie, Gesesew R., Das, Ramkrishna, Pandey, Ruchi, Ashok, N. M., Dubovsky, Pavol A.
Monthly Notices of the Royal Astronomical Society, 527 2024/01/1
https://ui.adsabs.harvard.edu/abs/2024MNRAS.527.1405H
We present the results of the investigation of the nova V1674 Her (2021), recognized as the swiftest classical nova, with t2 ~ 0.90 d. The distance to the nova is estimated to be 4.97 kpc. The mass and radius of the WD are calculated to be ~1.36 M⊙ and ~0.15 R⊕, respectively. Over the course of 1 month following the outburst, V1674 Her traversed distinct phases - pre-maxima, early decline, nebular, and coronal - displaying a remarkably swift transformation. The nebular lines emerged on day 10 making it the classical nova with the earliest observed commencement to date. We modelled the observed optical spectrum using the photoionization code CLOUDY. From the best-fitting model we deduced different physical and chemical parameters associated with the system. The temperature and luminosity of the central ionizing sources are found in the range of 1.99-2.34 × 105 K and 1.26-3.16 × 1038 erg s-1, respectively. Elements such as He , O , N , and Ne are found to be overabundant compared to solar abundance in both the nebular and coronal phases. According to the model, Fe II abundance diminishes while Ne abundance increases, potentially elucidating the rare hybrid transition between Fe and He/N nova classes. The ejected mass across all epochs spanned from 3.42 to 7.04 × 10-5 M⊙. Morpho-kinematic modelling utilizing SHAPE revealed that the nova V1674 Her possesses a bipolar structure with an equatorial ring at the centre and an inclination angle of i = 67 ± 1.5°.

3
TESS photometry of the nova eruption in V606 Vul: asymmetric photosphere and multiple ejections?
Sokolovsky, Kirill V., Aydi, Elias, Malanchev, Konstantin, Burke, Colin J., Mukai, Koji, Sokoloski, J. L., & al. (65)
arXiv e-prints, 2023/11/1
https://ui.adsabs.harvard.edu/abs/2023arXiv231104903S

4
Comprehensive Analysis of a Symbiotic Candidate V503 Her
Merc, Jaroslav, Gális, Rudolf, Wolf, Marek, Dubovský, Pavol A., Kára, Jan, Sims, Forrest, & al. (7)
The Astronomical Journal, 166 2023/08/1
https://ui.adsabs.harvard.edu/abs/2023AJ....166...65M
V503 Her was previously proposed as an eclipsing symbiotic candidate based on photometric behavior and spectroscopic appearance indicating the composite optical spectrum. To investigate its nature, we analyzed long-term photometric observations covering 100 yr of its photometric history and new low-resolution optical spectroscopic data, supplemented with the multifrequency measurements collected from several surveys and satellites. Based on the analysis presented in this paper, we claim that V503 Her is not an eclipsing binary star. The optical and infrared wavelengths are dominated by a K-type bright giant with an effective temperature of 4500 K, luminosity of 1900 L ⊙, and subsolar metallicity on the asymptotic giant branch showing semiregular complex multiperiodic pulsation behavior. V503 Her does not show the characteristics of strongly interacting symbiotic variables, but some pieces of evidence suggest that it could still be one of the "hidden" accreting-only symbiotic systems. However, the currently available data do not allow us to fully confirm or constrain the parameters of a possible companion.

5
V618 Sgr: galactic eclipsing symbiotic nova detected in repeated outbursts
Merc, J., Gális, R., Velez, P., Charbonnel, S., Garde, O., Le Dû, P., & al. (6)
Monthly Notices of the Royal Astronomical Society, 523 2023/07/1
https://ui.adsabs.harvard.edu/abs/2023MNRAS.523..163M
V618 Sgr was previously classified as an R CrB-type variable and later as a possible symbiotic star. Our study aims to analyse the nature of this target, which is currently undergoing significant brightening in properties similar to those of known symbiotic novae. We analyse literature information, photometric observations, and 35 new optical spectra. Our findings strongly suggest that V618 Sgr is an eclipsing symbiotic nova currently in outburst. Additionally, since the star has demonstrated at least two similar brightenings in the past, we propose that V618 Sgr could be the first known galactic symbiotic nova observed in repeated outbursts of this type and may host a relatively massive white dwarf.

6
Multi-wavelength spectroscopic study of shock-driven phenomena in explosive outbursts in symbiotic-like recurrent novae with an emphasis on RS Ophiuchi
Azzollini, Alessandra, Shore, Steven N., Kuin, Paul, Page, Kim L.
Astronomy and Astrophysics, 674 2023/06/1
https://ui.adsabs.harvard.edu/abs/2023A&A...674A.139A
 Aims: Our goal is to detail the development of RS Ophiuchi and the other Galactic symbiotic-like recurrent novae throughout their outburst and quiescence, with a particular emphasis on the propagation of the shock wave during the outburst of the binaries. Methods: The spectral analysis has been performed using archival data according to the features of the individual datasets. Swift grism spectra were reduced and extracted using a combination of the pre-existing UVOTPY Python routine and newly written pipelines in Matlab. Other datasets were directly available in reduced form, already corrected for instrumental or background contamination, and calibrated in wavelength and flux or intensity. The work on these was done through pipelines suited for reading the data and elaborating them to extract quantities of interest for the analysis. Results: We find striking similarities in different outbursts of the same object and for different novae. For example, RS Oph 2021 was almost identical to the 2006 outburst, despite having occurred at a different orbital phase with the observations made from a different line of sight through the red giant wind. Despite the intrinsically different properties of the binaries, striking similarities are found for different systems of the same class, for instance, the trend of the electron density over time during outburst appears to follow a general temporal development.

7
Shock shaping? Nebular spectroscopy of nova V906 Carinae
Harvey, É. J., Aydi, E., Izzo, L., Morisset, C., Darnley, M. J., Fitzgerald, K., & al. (4)
Monthly Notices of the Royal Astronomical Society, 521 2023/05/1
https://ui.adsabs.harvard.edu/abs/2023MNRAS.521.4750H
V906 Carinae was one of the best observed novae of recent times. It was a prolific dust producer and harboured shocks in the early evolving ejecta outflow. Here, we take a close look at the consequences of these early interactions through study of high-resolution Ultraviolet and Visual Echelle spectrograph spectroscopy of the nebular stage and extrapolate backwards to investigate how the final structure may have formed. A study of ejecta geometry and shaping history of the structure of the shell is undertaken following a spectral line $\rm {\small SHAPE}$ model fit. A search for spectral tracers of shocks in the nova ejecta is undertaken and an analysis of the ionized environment. Temperature, density, and abundance analyses of the evolving nova shell are presented.

8
Evidence for Multiple Shocks from the γ-Ray Emission of RS Ophiuchi
Diesing, Rebecca, Metzger, Brian D., Aydi, Elias, Chomiuk, Laura, Vurm, Indrek, Gupta, Siddhartha, & al. (1)
The Astrophysical Journal, 947 2023/04/1
https://ui.adsabs.harvard.edu/abs/2023ApJ...947...70D
In 2021 August, the Fermi Large Area Telescope, H.E.S.S., and MAGIC detected GeV and TeV γ-ray emission from an outburst of recurrent nova RS Ophiuchi. This detection represents the first very high-energy γ-rays observed from a nova, and it opens a new window to study particle acceleration. Both H.E.S.S. and MAGIC described the observed γ-rays as arising from a single, external shock. In this paper, we perform detailed, multi-zone modeling of RS Ophiuchi's 2021 outburst, including a self-consistent prescription for particle acceleration and magnetic field amplification. We demonstrate that, contrary to previous work, a single shock cannot simultaneously explain RS Ophiuchi's GeV and TeV emission, in particular the spectral shape and distinct light-curve peaks. Instead, we put forward a model involving multiple shocks that reproduces the observed γ-ray spectrum and temporal evolution. The simultaneous appearance of multiple distinct velocity components in the nova optical spectrum over the first several days of the outburst supports the presence of distinct shocks, which may arise either from the strong latitudinal dependence of the density of the external circumbinary medium (e.g., in the binary equatorial plane versus the poles) or due to internal collisions within the white dwarf ejecta (which power the γ-ray emission in classical novae).

9
Mass outflow from the symbiotic binary RS Oph during its 2021 outburst
Tomov, N. A., Tomova, M. T., Stoyanov, K. A., Bonev, T. R., Zamanov, R. K., Iliev, I. Kh., & al. (4)
Astronomy and Astrophysics, 671 2023/03/1
https://ui.adsabs.harvard.edu/abs/2023A&A...671A..49T
Context. RS Oph is a symbiotic recurrent nova containing a massive white dwarf with heavy mass loss during activity. In August 2021, it underwent its seventh optical eruption since the end of the 19th century. Aims: The goal of this work is to analyse the structure of the outflows from the outbursting object. Methods: Based on broad-band U, B, V, RC, and IC photometry and high-resolution Hα spectroscopy obtained at days 11-15 of the outburst, we derived some parameters of the system's components and outflows and their changes during our observation. Results: The effective temperature of a warm shell (pseudophotosphere) produced by the ejected material and occulting the hot component of the system was Teff = 15 000 ± 1000 K and the electron temperature of the nebula was Te = 17 000 ± 3000 K throughout the observations. The effective radius of the pseudophotosphere was Reff = 13.3 ± 2.0 R⊙ and the emission measure of the nebula EM = (9.50 ± 0.59) × 1061 cm−3 for day 11 and Reff = 10.3 ± 1.6 R⊙ and EM = (5.60 ± 0.35) × 1061 cm−3 for day 15. To provide this emission measure, the bolometric luminosity of the outbursting object must exceed its Eddington limit. The mass-loss rate of the outbursting object through its wind is much greater than through its streams. The total rate (from wind + streams) was less than (4-5) × 10-5 (d/1.6 kpc)3/2 M⊙ yr-1. The streams are not highly collimated. Their mean outflowing velocities are υb = −3680 ± 60 km s-1 for the approaching stream and υr = 3520 ± 50 km s-1 for the receding one if the orbit inclination is 50°.

10
Early Infrared and Visible Spectra from the 2022 Outburst of the Recurrent Novae U Scorpii
Rudy, Richard J., Subasavage, John P., Mauerhan, Jon C., Nofi, Larissa
Research Notes of the American Astronomical Society, 7 2023/02/1
https://ui.adsabs.harvard.edu/abs/2023RNAAS...7...26R
Spectroscopy from 0.46-2.5 μm is presented for the 2022 outburst of the recurrent nova U Scorpii from 2.54, 3.60, and 8.59 days after maximum light. During this period the spectra evolved from comparatively low excitation to the verge of displaying coronal lines. Between days 2.54 and 3.60, the nova showed a marked decrease in the low excitation lines of N I, O I, and Mg II , an increase in He I, the emergence of N III, and changes to the very broad line profiles. By day 8.59, the He I lines had been largely replaced by He II emission and most broad component were weak or undetectable. No optical coronal lines were observed during or immediately following the detection of infrared coronal lines by Banerjee et al.

11
Rebrightening of the symbiotic star V919 Sgr
Merc, J., Teyssier, F., Eldridge, C., Guarro Flo, J., Hambsch, F. -J., Kojima, T.
The Astronomer's Telegram, 16326 2023/11/1
https://ui.adsabs.harvard.edu/abs/2023ATel16326....1M
V919 Sgr is a relatively poorly studied symbiotic star despite being known since the seventies (Sanduleak & Stephenson, 1973; ApJ, 185, 899; Allen, 1978; MNRAS, 184, 601).

12
New burst of the symbiotic star V426 Sge (HBHA 1704-05)
Skopal, A., Shugarov, S., Shagatova, N., Teyssier, F., Boyd, D., Sims, F., & al. (5)
The Astronomer's Telegram, 16280 2023/10/1
https://ui.adsabs.harvard.edu/abs/2023ATel16280....1S
The star V426 Sge (HBHA 1704-05) started its activity in 1968 when it experienced a symbiotic nova outburst that ceased around 1990. The following quiescent phase was interrupted by a Z And-type outburst that commenced during the first decade of August 2018 (see Munari et al. 2018, ATel #11937; Skopal et al. 2020, A & A, 636, A77).

13
T CrB: the active spectroscopic state (2014-2023) is over
Teyssier, F., Hinnefeld, J. D., Boussin, C., Diabassoura, I., Guarro Flo, J., Sims, F., & al. (5)
The Astronomer's Telegram, 16109 2023/06/1
https://ui.adsabs.harvard.edu/abs/2023ATel16109....1T
The symbiotic recurrent nova (1866,1946) T CrB experienced a new active phase active phase since 2015 (Ilkiewicz & al., 2016, Munari & al., 2016) peaking in April 2016.

14
Persistent flickering of T CrB during the high activity state pre-nova outburst phase
Shore, S. N., Teyssier, F., ARAS Group
The Astronomer's Telegram, 15916 2023/02/1
https://ui.adsabs.harvard.edu/abs/2023ATel15916....1S
In 2015, the recurrent nova T Coronae Borealis entered an active state (Ilkiewicz et al. 2016) that is likely preceding its next outburst (Schaefer 2019, Luna etal.

15
ARAS Optical spectroscopy of GK Per in its current dwarf nova-like outburst
Shore, S. N., Teyssier, F., Guarro Flo, J., Sims, F., Bouttard, V.
The Astronomer's Telegram, 15858 2023/01/1
https://ui.adsabs.harvard.edu/abs/2023ATel15858....1S
The intermediate polar cataclysmic variable GK Per (Nova Per 1901) is currently undergoing a dwarf nova-like outburst, detected on 2022 Dec. 12 (JD JD 2459926) in the AAVSO lightcurve.

16
Gaia23clr: Outburst of the symbiotic star V2905 Sgr
Merc, J., Velez, P., Barker, H., Charbonnel, S., Garde, O., Du, P. Le, & al. (3)
The Astronomer's Telegram, 16257 2023/09/1
https://ui.adsabs.harvard.edu/abs/2023ATel16257....1M
The brightening of a transient Gaia23clr was announced as a Gaia Science Alert (GSA; Hodgkin et al., 2021; A & A, 652, A76) on September 21, 2023, indicating a 0.8 mag increase in brightness in the Gaia G filter.

17
Spectroscopic observations of the classical nova TCP J17525020-2024150
Garde, Olivier, Charbonnel, Stephane, Du, Pascal Le, Mulato, Lionel, Petit, Thomas, Pearce, Andrew, & al. (1)
The Astronomer's Telegram, 16135 2023/07/1
https://ui.adsabs.harvard.edu/abs/2023ATel16135....1G
We report early spectroscopic observations of transient TCP J17525020-2024150, reported in outburst by Andrew Pearce on 2023 Jul 15.459 (CBAT Transient follow-up reports).

18
Continued spectroscopic monitoring of V1716 Sco = Nova Sco 2023
Shore, Steve, Charbonnel, Stephane, Le Du, Pascal, Garde, Olivier, Mulato, Lionel, Petit, Thomas, & al. (1)
The Astronomer's Telegram, 16036 2023/05/1
https://ui.adsabs.harvard.edu/abs/2023ATel16036....1S
Our spectroscopic monitoring of the development of PNV J17224490-4137160 = V1716 Sco 2023 (ATel #16002, #16003, #16004, #16006,#16007, #16018 ) is continuing, using low resolution grism (R ~ 1000, 3550-8500A) and medium resolution echelle (R ~11000, 3847-7617A)(ATel #16006).

19
Continuing optical spectroscopic monitoring of PNV J17224490-4137160
Shore, Steve, Charbonnel, Stephane, Le Du, Pascal, Garde, Olivier, Mulato, Lionel, Petit, Thomas, & al. (1)
The Astronomer's Telegram, 16006 2023/04/1
https://ui.adsabs.harvard.edu/abs/2023ATel16006....1S
Our spectroscopic monitoring of the development of PNV J17224490-4137160 = Nova Sco 2023 (ATel #16002, #16003, #16004) is continuing, using medium resolution spectroscopy of the newly announced classical nova (and possible gamma-ray source) in Scorpius (ATel #16002, #16003, #16004, #16005).

20
Optical echelle spectrscopy of PNV J17224490-4137160
Shore, Steve, Charbonnel, Stephane, Le Du, Pascal, Garde, Olivier, Mulato, Lionel, Petit, Thomas
The Astronomer's Telegram, 16004 2023/04/1
https://ui.adsabs.harvard.edu/abs/2023ATel16004....1S
We report continuing medium resolution spectroscopy of the newly announced classical nova (and possible gamma-ray source) in Scorpius (ATel #16002, #16003).

21
Gaia23clr: Outburst of the symbiotic star V2905 Sgr
Merc, J., Velez, P., Barker, H., Charbonnel, S., Garde, O., Du, P. Le, & al. (3)
The Astronomer's Telegram, 16257 2023/09/1
https://ui.adsabs.harvard.edu/abs/2023ATel16257....1M
The brightening of a transient Gaia23clr was announced as a Gaia Science Alert (GSA; Hodgkin et al., 2021; A & A, 652, A76) on September 21, 2023, indicating a 0.8 mag increase in brightness in the Gaia G filter.