X-ray polarimetry is a long-standing missing piece in the puzzle of multiwavelenght study of high energy sources. The Imaging X-ray Polarimetry Explorer (IXPE) will fill this gap in our knowedge by adding polarization measurements to observables currently avaiable: energy, time, and position. IXPE, first proposed in response of an Announcement of Opportunity issued on 2014, was selected in the context of the NASA Astrophysics Small Explorer (SMEX) program in January 2017, and is a collaboration with the Italian Space Agency (ASI). Thanks to its Gas Pixel Detector imaging-capable polarimeter, IXPE will open new a new window in the understanding of particle acceleration processes, higly magnetized compact objects and the properties of scattering induced polarization. Here, the thecnical aspects of the mission and some of the scientific cases that IXPE will explore will be highlighted. Special attenton will be given to a selection of extended sources that IXPE will be able to study thanks its imaging capabilities.
{"title":"The Imaging X-ray Polarimetry Explorer (IXPE)","authors":"R. Ferrazzoli","doi":"10.22323/1.362.0068","DOIUrl":"https://doi.org/10.22323/1.362.0068","url":null,"abstract":"X-ray polarimetry is a long-standing missing piece in the puzzle of multiwavelenght study of high energy sources. The Imaging X-ray Polarimetry Explorer (IXPE) will fill this gap in our knowedge by adding polarization measurements to observables currently avaiable: energy, time, and position. IXPE, first proposed in response of an Announcement of Opportunity issued on 2014, was selected in the context of the NASA Astrophysics Small Explorer (SMEX) program in January 2017, and is a collaboration with the Italian Space Agency (ASI). Thanks to its Gas Pixel Detector imaging-capable polarimeter, IXPE will open new a new window in the understanding of particle acceleration processes, higly magnetized compact objects and the properties of scattering induced polarization. Here, the thecnical aspects of the mission and some of the scientific cases that IXPE will explore will be highlighted. Special attenton will be given to a selection of extended sources that IXPE will be able to study thanks its imaging capabilities.","PeriodicalId":265862,"journal":{"name":"Proceedings of Multifrequency Behaviour of High Energy Cosmic Sources - XIII — PoS(MULTIF2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114997412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I summarise the concluding remarks I gave at the Multifrequency Behaviour of High Energy Cosmic Sources - XIII Workshop. That was {it not} a summary talk and was meant to be provocative. I first give what I think the main message of the workshop was, then provide some (biased) highlights, touch upon the upcoming new facilities and the issues of ``quantity vs. quality'' and productivity in astronomy, and finally conclude with a look to the future. Astronomers who did not attend the workshop might still find the first two topics appealing and the last two thought-provoking.
{"title":"Concluding Remarks - II","authors":"P. Padovani","doi":"10.22323/1.362.0078","DOIUrl":"https://doi.org/10.22323/1.362.0078","url":null,"abstract":"I summarise the concluding remarks I gave at the Multifrequency Behaviour of High Energy Cosmic Sources - XIII Workshop. That was {it not} a summary talk and was meant to be provocative. I first give what I think the main message of the workshop was, then provide some (biased) highlights, touch upon the upcoming new facilities and the issues of ``quantity vs. quality'' and productivity in astronomy, and finally conclude with a look to the future. Astronomers who did not attend the workshop might still find the first two topics appealing and the last two thought-provoking.","PeriodicalId":265862,"journal":{"name":"Proceedings of Multifrequency Behaviour of High Energy Cosmic Sources - XIII — PoS(MULTIF2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133712280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gamma-ray binaries are a subclass of high-mass binary systems whose energy spectrum peaks at high energies (E$gtrsim$100 MeV) and extends to very high energies (E$gtrsim$100 GeV) $gamma$ rays. In this review we summarize properties of well-studied non-transient $gamma$-ray binaries as well as briefly discuss poorly known systems and transient systems hosting a microquasar. We discuss also theoretical models that have been used to describe spectral and timing characteristics of considered systems
{"title":"Gamma-ray binaries","authors":"M. Chernyakova, D. Malyshev","doi":"10.22323/1.362.0045","DOIUrl":"https://doi.org/10.22323/1.362.0045","url":null,"abstract":"Gamma-ray binaries are a subclass of high-mass binary systems whose energy spectrum peaks at high energies (E$gtrsim$100 MeV) and extends to very high energies (E$gtrsim$100 GeV) $gamma$ rays. In this review we summarize properties of well-studied non-transient $gamma$-ray binaries as well as briefly discuss poorly known systems and transient systems hosting a microquasar. We discuss also theoretical models that have been used to describe spectral and timing characteristics of considered systems","PeriodicalId":265862,"journal":{"name":"Proceedings of Multifrequency Behaviour of High Energy Cosmic Sources - XIII — PoS(MULTIF2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115450721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MAGIC has been exploring the sky at Very High Energy gamma-rays (50 GeV - 50 TeV) since 2004, operating first with a single telescope and from 2009 with two telescopes in stereoscopic mode. MAGIC has carried out a observational program involving fundamental physics and astrophysics topics. In this paper we present some of the most important results obtained by MAGIC, with a special emphasis in the most recent ones.
{"title":"MAGIC Highlights","authors":"J. Paredes, Magic Collaboration","doi":"10.22323/1.362.0043","DOIUrl":"https://doi.org/10.22323/1.362.0043","url":null,"abstract":"MAGIC has been exploring the sky at Very High Energy gamma-rays (50 GeV - 50 TeV) since 2004, operating first with a single telescope and from 2009 with two telescopes in stereoscopic mode. MAGIC has carried out a observational program involving fundamental physics and astrophysics topics. In this paper we present some of the most important results obtained by MAGIC, with a special emphasis in the most recent ones.","PeriodicalId":265862,"journal":{"name":"Proceedings of Multifrequency Behaviour of High Energy Cosmic Sources - XIII — PoS(MULTIF2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130456626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We present the results of simulations done with the code HARM-COOL developed in the CTP PAS Warsaw research group over the years 2017-2019. It is based in the original GR MHD scheme proposed by Gammie et al. (2003) for the simulation of Active Galactic Nucleus, but now it has been suited for the engine of a short Gamma Ray Burst event. We compute time-dependent evolution of a black hole accretion disk, in two-dimensional, axisymmetric scheme. The code includes neutrino cooling and accounts for nuclear structure of dense, degenerate matter. Free protons, neutrons, and electron-positron pairs form a neutron-rich, magnetically driven outflow that provides site for subsequent r-process nucleosynthesis. Here the heavy elements up to the Uranium and Gold are synthesized and may contribute to the chemical enrichment of the circum-burst medium. Their radio-active decay will give signal in lower energies in a timescale of weeks-months after the GRB prompt phase. In addition, the magnetic fields are responsible for the launching of ultra-relativistic jets along the rotation axis of the central black hole, according to the well-known Blandford-Znajek mechanism. These jets are sites of variable high energy emission in gamma rays. We find that the magnetic field and the black hole spin account for the observed variability timescales and jet energetics.
{"title":"Multi-messenger signals from short gamma ray bursts","authors":"A. Janiuk, K. Sapountzis, B. James, M. Kološ","doi":"10.22323/1.362.0059","DOIUrl":"https://doi.org/10.22323/1.362.0059","url":null,"abstract":"We present the results of simulations done with the code HARM-COOL developed in the CTP PAS Warsaw research group over the years 2017-2019. It is based in the original GR MHD scheme proposed by Gammie et al. (2003) for the simulation of Active Galactic Nucleus, but now it has been suited for the engine of a short Gamma Ray Burst event. \u0000We compute time-dependent evolution of a black hole accretion disk, in two-dimensional, axisymmetric scheme. The code includes neutrino cooling and accounts for nuclear structure of dense, degenerate matter. Free protons, neutrons, and electron-positron pairs form a neutron-rich, magnetically driven outflow that provides site for subsequent r-process nucleosynthesis. \u0000Here the heavy elements up to the Uranium and Gold are synthesized and may contribute to the chemical enrichment of the circum-burst medium. Their radio-active decay will give signal in lower energies in a timescale of weeks-months after the GRB prompt phase. \u0000In addition, the magnetic fields are responsible for the launching of ultra-relativistic jets along the rotation axis of the central black hole, according to the well-known Blandford-Znajek mechanism. These jets are sites of variable high energy emission in gamma rays. We find that the magnetic field and the black hole spin account for the observed variability timescales and jet energetics.","PeriodicalId":265862,"journal":{"name":"Proceedings of Multifrequency Behaviour of High Energy Cosmic Sources - XIII — PoS(MULTIF2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129859794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The review is devoted to consideration of possible observational consequences of modified gravity theories, suggested for explanation of the contemporary accelerated expansion of the universe. The major attention is paid to F(R)-models. It is shown that in systems with rising energy density high frequency and large amplitude oscillations of the curvature scalar, R(t), are induced. These oscillations lead to the production of elementary particles, which may be observed in the spectra of energetic cosmic rays. In the background of such oscillating solutions gravitation repulsion between finite-size objects becomes possible. Since the Lagrangian is a non-linear function of curvature, equations of motion become of higher (4th) order and exhibit very rich pattern of new physical effects. In particular, the evolution of density perturbations is strongly different from that in General Relativity, amplified due to both parametric resonance and anti-friction phenomena.
{"title":"Instabilities in modified theories of gravity","authors":"E. Arbuzova","doi":"10.22323/1.362.0026","DOIUrl":"https://doi.org/10.22323/1.362.0026","url":null,"abstract":"The review is devoted to consideration of possible observational consequences of modified gravity theories, suggested for explanation of the contemporary accelerated expansion of the universe. The major attention is paid to F(R)-models. It is shown that in systems with rising energy density high frequency and large amplitude oscillations of the curvature scalar, R(t), are induced. These oscillations lead to the production of elementary particles, which may be observed in the spectra of energetic cosmic rays. In the background of such oscillating solutions gravitation repulsion between finite-size objects becomes possible. Since the Lagrangian is a non-linear function of curvature, equations of motion become of higher (4th) order and exhibit very rich pattern of new physical effects. In particular, the evolution of density perturbations is strongly different from that in General Relativity, amplified due to both parametric resonance and anti-friction phenomena.","PeriodicalId":265862,"journal":{"name":"Proceedings of Multifrequency Behaviour of High Energy Cosmic Sources - XIII — PoS(MULTIF2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132549622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A review of the astronomical data of several last years on an astonishingly high amount of black holes in the contemporary and early ($zsim 10$) universe is presented. Also the data on the recently observed peculiar stars in the Galaxy are discussed. It is argued that practically all black holes in the universe are primordial (PBH) and suggested that an inverted picture of the galaxy formation is realized: supermassive black holes were formed prior to galaxy formation and subsequently seeded the latter. Possibilities of cosmological dark matter consisting of primordial black holes and of abundant cosmological antimatter are considered. A mechanism of 1993 anticipating all these phenomena and predicting an extended log-normal mass spectrum of PBH is described.
{"title":"Massive Primordial Black Holes","authors":"A. Dolgov","doi":"10.22323/1.362.0013","DOIUrl":"https://doi.org/10.22323/1.362.0013","url":null,"abstract":"A review of the astronomical data of several last years on an astonishingly high amount of black holes in the contemporary and early ($zsim 10$) universe is presented. Also the data on the recently observed peculiar stars in the Galaxy are discussed. It is argued that practically all black holes in the universe are primordial (PBH) and suggested that an inverted picture of the galaxy formation is realized: supermassive black holes were formed prior to galaxy formation and subsequently seeded the latter. Possibilities of cosmological dark matter consisting of primordial black holes and of abundant cosmological antimatter are considered. \u0000A mechanism of 1993 anticipating all these phenomena and predicting an extended log-normal mass spectrum of PBH is described.","PeriodicalId":265862,"journal":{"name":"Proceedings of Multifrequency Behaviour of High Energy Cosmic Sources - XIII — PoS(MULTIF2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131003200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The maximum mass of a neutron star has important implications across multiple research fields, including astrophysics, nuclear physics and gravitational wave astronomy. Compact binary millisecond pulsars (with orbital periods shorter than about a day) are a rapidly-growing pulsar population, and provide a good opportunity to search for the most massive neutron stars. Applying a new method to measure the velocity of both sides of the companion star, we previously found that the compact binary millisecond pulsar PSR J2215+5135 hosts one of the most massive neutron stars known to date, with a mass of 2.27$pm$0.16 M$_odot$ (Linares, Shahbaz & Casares, 2018). We reexamine the properties of the 0.33 M$_odot$ companion star, heated by the pulsar, and argue that irradiation in this "redback" binary is extreme yet stable, symmetric and not necessarily produced by an extended source. We also review the neutron star mass distribution in light of this and more recent discoveries. We compile a list of all (nine) systems with published evidence for super-massive neutron stars, with masses above 2 M$_odot$. We find that four of them are compact binary millisecond pulsars (one black widow, two redbacks and one redback candidate). This shows that compact binary millisecond pulsars are key to constraining the maximum mass of a neutron star.
{"title":"Super-Massive Neutron Stars and Compact Binary Millisecond Pulsars","authors":"M. Linares","doi":"10.22323/1.362.0023","DOIUrl":"https://doi.org/10.22323/1.362.0023","url":null,"abstract":"The maximum mass of a neutron star has important implications across multiple research fields, including astrophysics, nuclear physics and gravitational wave astronomy. Compact binary millisecond pulsars (with orbital periods shorter than about a day) are a rapidly-growing pulsar population, and provide a good opportunity to search for the most massive neutron stars. Applying a new method to measure the velocity of both sides of the companion star, we previously found that the compact binary millisecond pulsar PSR J2215+5135 hosts one of the most massive neutron stars known to date, with a mass of 2.27$pm$0.16 M$_odot$ (Linares, Shahbaz & Casares, 2018). We reexamine the properties of the 0.33 M$_odot$ companion star, heated by the pulsar, and argue that irradiation in this \"redback\" binary is extreme yet stable, symmetric and not necessarily produced by an extended source. We also review the neutron star mass distribution in light of this and more recent discoveries. We compile a list of all (nine) systems with published evidence for super-massive neutron stars, with masses above 2 M$_odot$. We find that four of them are compact binary millisecond pulsars (one black widow, two redbacks and one redback candidate). This shows that compact binary millisecond pulsars are key to constraining the maximum mass of a neutron star.","PeriodicalId":265862,"journal":{"name":"Proceedings of Multifrequency Behaviour of High Energy Cosmic Sources - XIII — PoS(MULTIF2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129974420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. L. Mart'inez-Aldama, S. Panda, B. Czerny, M. Zajavcek
In the near future, new surveys promise a significant increase in the number of quasars (QSO) at large redshifts. This will help to constrain the dark energy models using quasars. The Large Synoptic Survey Telescope (LSST) will cover over 10 million QSO in six photometric bands during its 10-year run. QSO will be monitored and subsequently analyzed using the photometric reverberation mapping (RM) technique. In low-redshift quasars, the combination of reverberation-mapped and spectroscopic results have provided important progress. However, there are still some facts which have to be taken into account for future results. It has been found that super-Eddington sources show time delays shorter than the expected from the well-known Radius-Luminosity ($Rmathrm{_{Hbeta}}-L_{5100}$) relation. Using a sample of 117 H$beta$ reverberation-mapped AGN with $0.02
在不久的将来，新的调查承诺在大红移中类星体(QSO)的数量将显著增加。这将有助于约束使用类星体的暗能量模型。大型天气巡天望远镜(LSST)将在其10年的运行中覆盖6个光度波段的超过1000万个QSO。QSO将被监测并随后使用光度混响映射(RM)技术进行分析。在低红移类星体中，混响映射和光谱结果的结合提供了重要的进展。然而，仍有一些事实必须考虑到未来的结果。已经发现，超级爱丁顿源显示的时间延迟比众所周知的半径-光度($Rmathrm{_{Hbeta}}-L_{5100}$)关系所预期的要短。利用117 H $beta$混响映射的AGN样本与$0.02
{"title":"Quasars from LSST as dark energy tracers: first steps","authors":"M. L. Mart'inez-Aldama, S. Panda, B. Czerny, M. Zajavcek","doi":"10.22323/1.362.0010","DOIUrl":"https://doi.org/10.22323/1.362.0010","url":null,"abstract":"In the near future, new surveys promise a significant increase in the number of quasars (QSO) at large redshifts. This will help to constrain the dark energy models using quasars. The Large Synoptic Survey Telescope (LSST) will cover over 10 million QSO in six photometric bands during its 10-year run. QSO will be monitored and subsequently analyzed using the photometric reverberation mapping (RM) technique. In low-redshift quasars, the combination of reverberation-mapped and spectroscopic results have provided important progress. However, there are still some facts which have to be taken into account for future results. It has been found that super-Eddington sources show time delays shorter than the expected from the well-known Radius-Luminosity ($Rmathrm{_{Hbeta}}-L_{5100}$) relation. Using a sample of 117 H$beta$ reverberation-mapped AGN with $0.02<z<0.9$, we propose a correction by the accretion rate effect recovering the classical $Rmathrm{_{Hbeta}}-L_{5100}$ relation. We determined the cosmological constants, which are in agreement with $Lambda$-Cold Dark Matter model within 2$sigma$ confidence level, which is still not suitable for testing possible departures from the standard model. Upcoming LSST data will decrease the uncertainties in the dark energy determination using reverberation-mapped sources, particularly at high redshifts. We show the first steps in the modeling of the expected light curves for H$beta$ and MgII.","PeriodicalId":265862,"journal":{"name":"Proceedings of Multifrequency Behaviour of High Energy Cosmic Sources - XIII — PoS(MULTIF2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133138966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Borkar, A. Eckart, C. Straubmeier, N. Sabha, Laurant O. Sjouwerman, V. Karas, D. Kunneriath, L. Moser, S. Britzen, M. Valencia-Schneider, A. Donea, A. Zensus
We present results of 3 mm observations of SiO maser sources in the Galactic Centre (GC) from observations with the Australia Telescope Compact Array between $2010-2014$, along the transitions of the SiO molecule at $v = 1, J = 2-1$ at 86.243 GHz and $v = 2, J = 2-1$ at 85.640 GHz. We also present the results of the 3 mm observations with Atacama Large Millimeter/Submillimeter Array (ALMA). We detected 5 maser sources from the ATCA data, IRS 7, IRS 9, IRS 10EE, IRS 12N, and IRS 28; and 20 sources from the ALMA data including 4 new sources. These sources are predominantly late-type giants or emission line stars with strong circumstellar maser emission. We analyse these sources and calculate their proper motions. We also study the variability of the maser emission. IRS 7, IRS 12N and IRS 28 exhibit long period variability of the order of $1 - 2$ years, while other sources show steady increase or decrease in flux density and irregular variability over observation timescales. This behaviour is consistent with the previous observations.
{"title":"Observations of the 86 GHz SiO maser sources in the Central Parsec of the Galactic Centre","authors":"A. Borkar, A. Eckart, C. Straubmeier, N. Sabha, Laurant O. Sjouwerman, V. Karas, D. Kunneriath, L. Moser, S. Britzen, M. Valencia-Schneider, A. Donea, A. Zensus","doi":"10.22323/1.362.0033","DOIUrl":"https://doi.org/10.22323/1.362.0033","url":null,"abstract":"We present results of 3 mm observations of SiO maser sources in the Galactic Centre (GC) from observations with the Australia Telescope Compact Array between $2010-2014$, along the transitions of the SiO molecule at $v = 1, J = 2-1$ at 86.243 GHz and $v = 2, J = 2-1$ at 85.640 GHz. We also present the results of the 3 mm observations with Atacama Large Millimeter/Submillimeter Array (ALMA). We detected 5 maser sources from the ATCA data, IRS 7, IRS 9, IRS 10EE, IRS 12N, and IRS 28; and 20 sources from the ALMA data including 4 new sources. These sources are predominantly late-type giants or emission line stars with strong circumstellar maser emission. We analyse these sources and calculate their proper motions. We also study the variability of the maser emission. IRS 7, IRS 12N and IRS 28 exhibit long period variability of the order of $1 - 2$ years, while other sources show steady increase or decrease in flux density and irregular variability over observation timescales. This behaviour is consistent with the previous observations.","PeriodicalId":265862,"journal":{"name":"Proceedings of Multifrequency Behaviour of High Energy Cosmic Sources - XIII — PoS(MULTIF2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123569887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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