Astronomische Nachrichten最新文献

{"title":"Preface: Workshop on matter, astrophysics, gravitation, ions and cosmology—MAGIC23","authors":"César A. Zen Vasconcellos,&nbsp;Dimiter Hadjimichef,&nbsp;Magno Machado,&nbsp;Benno Bodmann,&nbsp;Marcelo Netz-Marzola,&nbsp;Geovane Naysinger,&nbsp;Mariana Vargas Magaña,&nbsp;Peter O. Hess,&nbsp;Horst Stöcker,&nbsp;Steven Gullberg,&nbsp;Remo Ruffini","doi":"10.1002/asna.20240029","DOIUrl":"10.1002/asna.20240029","url":null,"abstract":"<p>We outline our experience in organizing the first edition of the Workshop on Matter, Astrophysics, Gravitation, Ions and Cosmology, held in virtual and in-person format, denominated <i>MAGIC23</i>, held from 6 to 10 March, 2023, in <i>Praia do Rosa, Santa Catarina, Brazil</i>. The event aimed to bring together leading academic scientists, professors, students, and research scholars for exchanging experiences and discuss the most recent innovations, trends, practical challenges, and experimental and theoretical solutions adopted in the investigation fields within the scope of the meeting. The workshop offered to the participants a platform for scientific and academic projects, partnerships, and presentation of high-quality research contributions describing original and unpublished results on topics related to matter, astrophysics, gravitation, ions, and cosmology.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 2-3","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140200602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterizing the dynamical magnetosphere of the extremely slowly rotating magnetic O9.7 V star HD 54879 using rotational modulation of the Hα profile","authors":"Manfred Küker,&nbsp;S. P. Järvinen,&nbsp;S. Hubrig,&nbsp;Ilya Ilyin,&nbsp;M. Schöller","doi":"10.1002/asna.20230169","DOIUrl":"10.1002/asna.20230169","url":null,"abstract":"<p>The magnetic field in the O9.7 V star HD 54879 has been monitored for almost a decade. Spectropolarimetric observations reveal a rather strong mean longitudinal magnetic field that varies with a period of about 7.41 years. Observations in the H<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>α</mi>\u0000 </mrow>\u0000 <annotation>$$ alpha $$</annotation>\u0000 </semantics></math> line show a variation with the same period, while the H<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>β</mi>\u0000 </mrow>\u0000 <annotation>$$ beta $$</annotation>\u0000 </semantics></math> line shows only little variation. Assuming the periodic variation to be caused by a slow rotation and a dipolar magnetic field, we find a magnetic field strength of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>≥</mo>\u0000 </mrow>\u0000 <annotation>$$ ge $$</annotation>\u0000 </semantics></math>2 kG at the magnetic poles. With the relatively low mass loss rate of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msup>\u0000 <mn>10</mn>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>9</mn>\u0000 </mrow>\u0000 </msup>\u0000 <msub>\u0000 <mi>M</mi>\u0000 <mo>⊙</mo>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {10}^{-9}{M}_{odot } $$</annotation>\u0000 </semantics></math> year⁻¹, this star is a case of extremely strong magnetic confinement. Both theoretical arguments and numerical simulations indicate the presence of an extended disk of increased gas density in the equatorial plane of the magnetic field, where gas from the line-driven stellar wind is trapped. This disk is likely to be the origin of the observed H<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>α</mi>\u0000 </mrow>\u0000 <annotation>$$ alpha $$</annotation>\u0000 </semantics></math> emission, which peaks together with the strongest line-of-sight magnetic field. The profile of the H<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>α</mi>\u0000 </mrow>\u0000 <annotation>$$ alpha $$</annotation>\u0000 </semantics></math> line is resolved in several components and shows a remarkable variability with the rotation period.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 4","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.20230169","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140200504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Issue Information: Astron. Nachr. 1/2024","authors":"","doi":"10.1002/asna.20249001","DOIUrl":"https://doi.org/10.1002/asna.20249001","url":null,"abstract":"","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.20249001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140123681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cover Picture: Astron. Nachr. 1/2024","authors":"L. R. Bedin,&nbsp;J. Dietrich,&nbsp;A. J. Burgasser,&nbsp;D. Apai,&nbsp;M. Libralato,&nbsp;M. Griggio,&nbsp;C. Fontanive,&nbsp;D. Pourbaix","doi":"10.1002/asna.20249011","DOIUrl":"https://doi.org/10.1002/asna.20249011","url":null,"abstract":"<p>Motion on the sky of the brown dwarf binary system Luhman 16 AB. At a distance of less than 2 pc, it is known as the nearest pair of this type to Earth. (Top:) The entire 4.7ʹ × 4ʹ region surrounding Luhman 16 AB, as monitored by HST. (Bottom:) Zoom-in of the 25ʺ × 7ʺ rectangular region indicated in red in the top panel, showing the complete trajectory in the sky of Luhman 16 A and B during the period of 7.4 years monitored by recent HST observations. The astrometric solution for the Luhman AB barycenter, with and without parallax is indicated by blue and magenta curves, respectively. For details about the search for a suspected exoplanet orbiting one of the brown dwarf components see Bedin <i>et al</i>., this issue, e230158.\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure>\u0000 </p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.20249011","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140123680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"HST astrometry of the closest brown dwarfs-II. Improved parameters and constraints on a third body","authors":"L. R. Bedin,&nbsp;J. Dietrich,&nbsp;A. J. Burgasser,&nbsp;D. Apai,&nbsp;M. Libralato,&nbsp;M. Griggio,&nbsp;C. Fontanive,&nbsp;D. Pourbaix","doi":"10.1002/asna.20230158","DOIUrl":"10.1002/asna.20230158","url":null,"abstract":"&lt;p&gt;Located at less than two pc away, Luhman 16 AB (WISE J104915.57-531906.1) is the closest pair of brown dwarfs and the third closest “stellar” system to Earth. An exoplanet candidate in the Luhman 16 binary system was reported in 2017 based on a weak astrometric signature in the analysis of 12 HST epochs. An additional epoch collected in 2018 and re-analysis of the data with more advanced methods further increased the significance level of the candidate, consistent with a Neptune-mass exoplanet orbiting one of the Luhman 16 brown dwarf components. We report the joint analysis of these previous data together with two new astrometric &lt;i&gt;HST&lt;/i&gt; epochs we obtained to confirm or disprove this astrometric signature. Our new analysis rules out the presence of a planet orbiting one component of the Luhman 16 AB system for masses &lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;ℳ&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ mathrm{mathcal{M}} $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; &lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;≳&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ gtrsim $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; 1.5 M&lt;sub&gt;♆&lt;/sub&gt; (Neptune masses) and periods between 400 and 5000 days. However, the presence of third bodies with masses &lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;ℳ&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ mathrm{mathcal{M}} $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; &lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;≲&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ lesssim $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; 3 M&lt;sub&gt;♆&lt;/sub&gt; and periods between 2 and 400 days (&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;∼&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ sim $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;1.1 years) cannot be excluded. Our measurements make significant improvements to the characterization of this sub-stellar binary, including its mass-ratio 0.8305 &lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;±&lt;/mo&gt;\u0000 &lt;mn&gt;0.0006&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ pm 0.0006 $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, individual component masses 35.4&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;±&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ pm $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;0.2 M&lt;sub&gt;Ꝝ&lt;/sub&gt; and 29.4&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;±&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ pm $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;0.2 M&lt;sub&gt;Ꝝ&lt;/sub&gt; (Jupiter masses), and parallax distance 1.9960 pc &lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;±&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140073082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spectroscopic and photometric behavior of LP Ori","authors":"Aslı Elmaslı,&nbsp;Kübra Özge Ünal,&nbsp;Doğus Özuyar","doi":"10.1002/asna.20240022","DOIUrl":"10.1002/asna.20240022","url":null,"abstract":"<p>We performed spectroscopic and photometric analyses on the early B-type LP Ori young stellar object located in the Orion Nebula. The high-resolution spectra of LP Ori was obtained at the Ankara University Kreiken Observatory in 2023, while all spectra recorded over the past 19 years were extracted from the ESO and ESPaDOnS archives. In these spectra of LP Ori, there is typically an emission observed in the core of the Balmer profile. This structure is accompanied by a <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>∼</mo>\u0000 </mrow>\u0000 <annotation>$$ sim $$</annotation>\u0000 </semantics></math>14-year interval inverse P-Cygni repetition superimposed on the Balmer profile. Additionally, an emission in the <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>λ</mi>\u0000 </mrow>\u0000 <annotation>$$ lambda $$</annotation>\u0000 </semantics></math>5,875 He I line is visible in the spectra in the year 2023. When this emission is considered together with the inverse P-Cygni structures, these observations suggest that LP Ori is a Herbig Ae/Be star. The abundance pattern of LP Ori is close to solar with the exception of a slightly rich helium and slightly poor aluminum abundance. Additionally, the spectral energy distribution of LP Ori was constructed to confirm the infrared excess caused by its circumstellar disk. Furthermore, the photometric analysis performed on the TESS observations of LP Ori shows significant photometric variability and the frequency analysis reveals a <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>β</mi>\u0000 </mrow>\u0000 <annotation>$$ beta $$</annotation>\u0000 </semantics></math> Cephei star in its forthcoming evolution.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 5","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140002246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the chemical composition of the evolved very bright metal-poor star HD 1936","authors":"Şeyma Çalışkan,&nbsp;Jannat Mushreq Kamil Alazzawi,&nbsp;Yahya Nasolo","doi":"10.1002/asna.20230048","DOIUrl":"10.1002/asna.20230048","url":null,"abstract":"<p>We present chemical abundances of the very bright metal-poor star HD 1936 based on high-resolution and high SNR spectra from AUKR. We obtain the abundances of 29 atomic species with atomic numbers between 3 and 63. In this context, the derived lithium abundance of 1.01 is consistent with the thin Li plateau observed in lower red giant branch stars. The star is a carbon-normal with a ratio of −0.31, just like other low-luminosity red giants on the thin Li plateau. We find the ratios of [Eu/Fe] = 0.43 and [Ba/Eu] = −0.64, indicating very little s-process contamination. These ratios allow us to classify the star as a moderately r-process-enhanced (r-I) metal-poor star for the first time. It is worth mentioning that the star has a metallicity of −1.74, a [Cu/Fe] of −0.74, a [Zn/Fe] of 0.04, and a [Mg/C] of 0.69. The results suggest that it may be a second-generation star formed in a multi-enriched environment, rather than being a descendant of very massive first-generation stars. A last point worth mentioning is the possibility that HD 1936 may host a sub-stellar component with a mass of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>18.35</mn>\u0000 <msub>\u0000 <mi>M</mi>\u0000 <mi>J</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ 18.35{M}_{mathrm{J}} $$</annotation>\u0000 </semantics></math>. Although our study does not confirm or deny this, we briefly discuss the possibility of the star hosting a planet.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 4","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140001797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Calculated brightness temperatures of solar structures compared with ALMA and Metsähovi measurements","authors":"Filip Matković,&nbsp;Roman Brajša,&nbsp;Matej Kuhar,&nbsp;Arnold O. Benz,&nbsp;Hans -G. Ludwig,&nbsp;Caius L. Selhorst,&nbsp;Ivica Skokić,&nbsp;Davor Sudar,&nbsp;Arnold Hanslmeier","doi":"10.1002/asna.20230149","DOIUrl":"10.1002/asna.20230149","url":null,"abstract":"<p>The Atacama Large Millimeter/submillimeter Array (ALMA) allows for solar observations in the wavelength range of 0.3–10 mm, giving us a new view of the chromosphere. The measured brightness temperature at various frequencies can be fitted with theoretical models of density and temperature versus height. We use the available ALMA and Metsähovi measurements of selected solar structures (quiet sun (QS), active regions (AR) devoid of sunspots, and coronal holes (CH)). The measured QS brightness temperature in the ALMA wavelength range agrees well with the predictions of the semiempirical Avrett–Tian–Landi–Curdt–Wülser (ATLCW) model, better than previous models such as the Avrett–Loeser (AL) or Fontenla–Avrett–Loeser model (FAL). We scaled the ATLCW model in density and temperature to fit the observations of the other structures. For ARs, the fitted models require 9%–13% higher electron densities and 9%–10% higher electron temperatures, consistent with expectations. The CH fitted models require electron densities 2%–40% lower than the QS level, while the predicted electron temperatures, although somewhat lower, do not deviate significantly from the QS model. Despite the limitations of the one-dimensional ATLCW model, we confirm that this model and its appropriate adaptations are sufficient for describing the basic physical properties of the solar structures.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 5","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140001977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lessons from the apparent peculiar nature of the star TYC 6544-3483-1","authors":"Josep Martí,&nbsp;Pedro L. Luque-Escamilla,&nbsp;Benito Marcote,&nbsp;Daniel del Ser,&nbsp;Gustavo E. Romero,&nbsp;Cintia S. Peri","doi":"10.1002/asna.20230128","DOIUrl":"10.1002/asna.20230128","url":null,"abstract":"<p>We report a radio and optical study of the star TYC 6544-3483-1 originally selected as a follow-up target in the course of our efforts to cross-identify Galactic high-energy sources. The star by itself finally turned out to be a very ordinary main-sequence star despite the initial expectations that apparently pointed to the contrary. We found that its, at first glance, exotic properties arise as a combined consequence of the limited angular resolution of the radio and optical databases being used. Our preliminary astrophysical interpretation was strongly hampered by the presence of unexpected optical variables inside both the photometric and background apertures. While such an ill-posed situation is not a frequent one, we believe that our experience is worth sharing with the community to raise a word of caution and help to avoid similar misleading results, especially when dealing with modern TESS data.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 4","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.20230128","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140002024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SNe 2019vxm and 2020tlf: two luminous type II Supernovae with signatures of circumstellar interaction","authors":"Dmitry Yu Tsvetkov,&nbsp;Nickolay N. Pavlyuk,&nbsp;Alexandr V. Dodin,&nbsp;Nickolay I. Shatsky,&nbsp;Sergey A. Potanin,&nbsp;Nataliya P. Ikonnikova,&nbsp;Marina A. Burlak,&nbsp;Aleksandr A. Belinskii,&nbsp;Igor M. Volkov,&nbsp;Vsevolod A. Echeistov","doi":"10.1002/asna.20230166","DOIUrl":"10.1002/asna.20230166","url":null,"abstract":"<p>We present optical spectroscopic and photometric observations of type II SNe 2019vxm and 2020tlf. The photometric monitoring of SN 2019vxm continued for 592 days, two spectra were collected. SN 2020tlf was observed for 163 days and we obtained one spectra. The maximum luminosity of both SNe is high: <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>M</mi>\u0000 <mi>V</mi>\u0000 </msub>\u0000 <mo>=</mo>\u0000 <mo>−</mo>\u0000 <mn>20.0</mn>\u0000 <mo>,</mo>\u0000 <mo>−</mo>\u0000 <mn>18.33</mn>\u0000 </mrow>\u0000 <annotation>$$ {M}_V=-20.0,-18.33 $$</annotation>\u0000 </semantics></math> mag for SN 2019vxm and SN 2020tlf, respectively. SN 2019vxm displays typical for most of SNe IIn photometric evolution: long rise to the maximum and slow brightness decline with several changes of the decline rate. The light curve of SN 2020tlf shows it may be considered as an intermediate object between classes II-P and II-L. The spectral evolution of SN 2019vxm was typical for SNe IIn, while for SN 2020tlf only weak signs of circumstellar interaction were observed at maximum light.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"345 4","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139952143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}