Astrophysical Bulletin最新文献

{"title":"Estimates of Atmospheric Mass Loss for Two Planets of the Young Solar Analog HD 109833","authors":"I. S. Savanov","doi":"10.1134/S1990341325600437","DOIUrl":"10.1134/S1990341325600437","url":null,"abstract":"<p>We present the results of a further investigation of the planetary\u0000system HD 109833, whose central star is a young, active solar\u0000analog, presumably a member of the Lower Centaurus Crux\u0000association (age: <span>(27pm 3)</span> Myr). Using digitized photographic\u0000plates from the Digital Access to a Sky Century@Harvard project\u0000(providing data on HD 109833 spanning a 100 year observation\u0000period) we made an additional attempt to study possible activity\u0000cycles of the star. Taking into account all uncertainties, it\u0000should be noted that the derived estimates of the activity cycle\u0000period <span>(P_{textrm{cycl}})</span> (including the earlier value obtained\u0000from ASAS-3 data, <span>(P_{textrm{cycl}}=5.3)</span> years) are on the edge\u0000of statistical reliability. Based on measurements of the\u0000chromospheric activity index <span>(log R^{prime}_{HK})</span> for\u0000HD 109833 from the updated HARP SRV database and its empirical\u0000relation with <span>(log F_{textrm{XUV}})</span>, we estimated the XUV\u0000photon flux to be <span>(2.0times 10^{29})</span> erg s<span>({}^{-1})</span>. The\u0000exoplanets HD 109833 b and c are located in the overlapping\u0000region of two distinct populations on the ‘‘mass–radius’’\u0000diagram: rocky planets and planets rich in volatile compounds. We\u0000present calculations of atmospheric mass loss rates <span>(dot{M})</span> for\u0000HD 109833 b and c based on both the energy-limited escape model\u0000(EL) and the hydrodynamic approximation model (HA), using\u0000different planetary mass estimates. We also provide the ratios of\u0000mass loss rates <span>(dot{M})</span> obtained from EL and HA models (Ratio),\u0000and the values of the Jeans parameter <span>(Lambda)</span>. It is suggested\u0000that the HA model significantly underestimates <span>(dot{M})</span> in the\u0000case of rocky planets, rendering this model inapplicable for such\u0000high values of <span>(Lambda)</span>. Our results are in reasonable agreement\u0000with those of Foster et al. (2022), which describe the general\u0000behavior of <span>(dot{M})</span>, and fall within the observed spread of this\u0000parameter.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 3","pages":"442 - 448"},"PeriodicalIF":1.4,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659419","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":"Cosmological Observational Tests in the JWST ERA. I: Angular Size–Redshift","authors":"A. A. Raikov,&nbsp;V. V. Tsymbal,&nbsp;N. Yu. Lovyagin","doi":"10.1134/S1990341325600383","DOIUrl":"10.1134/S1990341325600383","url":null,"abstract":"<p>This study is devoted to the cosmological ‘‘angular size–redshift’’ test. An analysis was performed of the angular and linear sizes of galaxies from the new ASTRODEEP-JWST catalog containing over 500 000 objects at high redshifts (up to <span>(zsim 20)</span> photometrically determined and up to <span>(zsim 14)</span> spectroscopically determined). For calculations, 6860 galaxies with reliably determined spectroscopic redshifts and 319 771 galaxies with known photometric redshifts were used. The linear sizes of galaxies were computed within the framework of two cosmological models—the standard (<span>(Lambda)</span>CDM) model and one of the static models (the so-called ‘‘tired light’’ model). We have shown that within the framework of the <span>(Lambda)</span>CDM model, a significant evolution of the linear sizes of galaxies is observed, with the evolutionary rate closely matching the rate of the cosmic expansion. In contrast, in the static model, the characteristic linear sizes of galaxies exhibit almost no evolution with increasing <span>(z)</span>.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 3","pages":"337 - 347"},"PeriodicalIF":1.4,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659393","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":"Optical and Physical Characteristics of the FL Psc Dwarf Nova before and after the 2023 Superoutburst","authors":"V. V. Shimansky,&nbsp;N. V. Borisov,&nbsp;A. A. Dudnik,&nbsp;A. I. Kolbin,&nbsp;E. D. Motorina,&nbsp;N. N. Shimanskaya,&nbsp;A. S. Vinokurov","doi":"10.1134/S1990341325600164","DOIUrl":"10.1134/S1990341325600164","url":null,"abstract":"<p>The paper studies the characteristics of optical emission\u0000formation and determines the fundamental parameters of the FL Psc\u0000dwarf nova for the epochs before and after its superoutburst in\u00002023. Moderate-resolution spectral sets were obtained in 2021,\u00002023 and 2024 with the BTA-6 telescope of the SAO RAS.\u0000Observations in all epochs are dominated by the continuous\u0000spectrum of the white dwarf (WD) with H I, He I, He II, C II,\u0000Mg I, Ca I, Ca II, Fe I emissions and Fe II from the\u0000accretion disk and a bright spot at its outer radius. Changes in\u0000emission intensities and their Doppler half-widths showed that\u0000during the transition from the relaxation stage to quiescence,\u0000the zone of maximum radiation shifted to the periphery of the\u0000disk, and the temperature in it decreased to <span>(T_{e}&lt;8000)</span> K. An\u0000analysis of the observed spectra for three epochs was performed\u0000using model flux (i.e. in flux units) and normalized spectra of\u0000the WD and a modified method for determining the parameters of\u0000their atmospheres. As a result, the following estimates of the\u0000accretor’s temperature were obtained for a single surface gravity\u0000value <span>(log g=8.26pm 0.13)</span>: <span>(T_{textrm{eff}}=17,700pm 1400)</span> K, <span>(26,700pm 1900)</span> K and <span>(19,600pm 1300)</span> K in 2021,\u00002023 and 2024, respectively. It is shown that the observed\u0000systematic variations in the brightness of FL Psc after the end of\u0000the outburst are correctly explained by changes in the WD\u0000temperature, taking into account the additional contribution of\u0000emission lines. Based on the parameters found for the accretor’s\u0000atmosphere, the complete set of fundamental parameters of the\u0000system is refined. Its Doppler tomography showed that 1.3 years\u0000after the outburst, the accretion disk remained optically thick in\u0000the H I lines, but became optically thin in the lines of other\u0000elements. Analysis of the FL Psc maps suggests that the H I,\u0000He I and He II emissions are formed predominantly under\u0000thermalization conditions, while the Ca II and Fe II  emissions\u0000are formed under the influence of the fluorescence effects of soft\u0000ultraviolet radiation from the WD in the accretion disk and the\u0000surrounding gaseous envelope.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 3","pages":"428 - 441"},"PeriodicalIF":1.4,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659394","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":"Disk Population of Type II Cepheids in the Galaxy Based on Gaia DR3 Data","authors":"A. S. Rastorguev,&nbsp;M. V. Zabolotskikh","doi":"10.1134/S1990341325600358","DOIUrl":"10.1134/S1990341325600358","url":null,"abstract":"<p>Galactic orbital parameters of 519 type II Cepheids classified as\u0000BL Her, W Vir and RV Tau variable stars were calculated using\u0000Bayesian distances, proper motions, and Gaia DR3 radial\u0000velocities. It is shown that at least 27 BL Her type variables out\u0000of 100, 17 W Vir type variables out of 308 and 8 RV Tau type\u0000variables out of 111 are characterized by a spatial distribution\u0000and galactic orbital parameters typical of the population of the\u0000thin/old disk of the Galaxy. At the same time, their luminosities\u0000are significantly lower than those of classical Cepheids (DCEP),\u0000and correspond to the luminosities of type II Cepheids. It is\u0000suggested that the region of the instability strip occupied by\u0000short-period Cepheids of the BL Her type may contain stars of the\u0000old disk with initial masses of about <span>(0.95 M_{odot})</span>, which\u0000evolved from the main sequence to the stage of the onset of helium\u0000burning in the core and reached the instability strip over a time\u0000of about 9 Gyr. The presence of evolutionary ‘‘loops’’ explains\u0000the existence of a number of BL Her type Cepheids, which\u0000demonstrate an evolutionary decrease in period. Thus, both\u0000low-mass stars in the phase of evolution of a double-layer source\u0000and stars at the stage of the onset of helium burning in the core\u0000with a larger initial mass can coexist in the instability strip of\u0000BL Her variables. To refine the classification of type II\u0000Cepheids, more detailed evolutionary and pulsation calculations\u0000and additional comprehensive studies are needed, including, for\u0000example, estimates of pulsation radii.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 3","pages":"456 - 467"},"PeriodicalIF":1.4,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659395","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":"Statistics of Coronal Mass Ejections in Solar Flares with Helioseismic Response","authors":"I. N. Sharykin,&nbsp;I. V. Zimovets","doi":"10.1134/S1990341324600856","DOIUrl":"10.1134/S1990341324600856","url":null,"abstract":"<p>This paper presents the results of a statistical analysis of the properties of coronal mass ejections (CMEs) associated with solar flares that exhibit a helioseismic response (‘‘sunquakes’’) in comparison with flares that do not show photospheric disturbances. The analysis is based on observations of the solar corona in the ultraviolet range (from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, SDO/AIA) and the visible range (from the Large Angle Spectroscopic Coronagraph on board the Solar and Heliospheric Observatory, SOHO/LASCO). We considered samples of flares with different lower thresholds based on the Geostationary Operational Environmental Satellites (GOES) classification: above M1.0, M5.0, and M7.0. A correlation analysis was also carried out between CME parameters and the total energy of the sunquakes. Additionally, for flares above M7.0-class, information on the presence of radio bursts across a wide range of wavelengths, as well as hard X-ray emission, was analyzed. It was found that CMEs accompanying flares with a helioseismic response tend to have higher velocities in the lower corona (according to AIA data) compared to flares without photospheric disturbances. The distribution of CME masses is approximately the same regardless of the presence or absence of sunquakes during the flares. An analysis of dimming properties showed that they are more impulsive in terms of temporal dynamics in flares with sunquakes. CMEs in flares above M7.0-class that exhibit helioseismic responses are less massive and slower in the outer corona according to LASCO data. The correlation analysis did not reveal strong relationships between acoustic energy and CME parameters based on AIA observations, but for several parameters (kinetic energy, CME mass, and dimming depth), statistically significant correlations were identified according to the <span>(t)</span>-criterion. In contrast to flares with sunquakes, there was an almost complete absence of type III radio bursts and a rare occurrence of type II bursts in the M7.0-class flares without photospheric disturbances. The spectral peak of microwave bursts tends to occur at higher frequencies in flares with sunquakes than in those without. According to our analysis, flares with sunquakes likely possess the ability to efficiently generate fast coronal dimmings and shock waves, even in the presence of poorly developed CMEs in the upper corona (in comparison to flares without photospheric disturbances). These events are also characterized by pronounced signatures of electron acceleration, with particles escaping the acceleration region both toward the solar surface and outward from it. In our view, this indicates that the possibility of an eruptive origin for sunquakes cannot be ruled out. Accelerated electrons may act as both the primary and secondary agents responsible for initiating the photospheric perturbation.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 2","pages":"294 - 311"},"PeriodicalIF":1.4,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144888069","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":"Photometric Stability of an EMCCD Camera at 1-s Exposures","authors":"I. V. Afanasieva,&nbsp;V. G. Orlov,&nbsp;V. I. Ardilanov,&nbsp;V. A. Murzin,&nbsp;D. V. Oparin,&nbsp;A. N. Burenkov","doi":"10.1134/S1990341324600832","DOIUrl":"10.1134/S1990341324600832","url":null,"abstract":"<p>We present the results of testing an iXon Ultra 888 EMCCD camera to determine the operating parameters for short-exposure photometry of stars. As a result of the testing, those camera modes were selected in which the temporal instability of the electron multiplication charge does not significantly affect the light curves. In addition, the photometry of the eclipsing variable star ZTF J 0038+2030, obtained with the Zeiss-1000 telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences, is presented. We have shown the advantages and disadvantages of 1-s exposures for studying variable stars.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 2","pages":"312 - 320"},"PeriodicalIF":1.4,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144888112","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":"W-DIMM: Test Measurements of Optical Turbulence Parameters at the Crimean Station of Sternberg Astronomical Institute","authors":"S. A. Potanin,&nbsp;A. Yu. Shikhovtsev,&nbsp;M. V. Kornilov,&nbsp;E. A. Kopylov,&nbsp;I. A. Gorbunov,&nbsp;A. V. Lyutyi,&nbsp;A. D. Savvin,&nbsp;M. E. Sachkov,&nbsp;M. V. Potanina","doi":"10.1134/S1990341324601023","DOIUrl":"10.1134/S1990341324601023","url":null,"abstract":"<p>A mobile W-DIMM device was used to measure seeing at the Crimean station of Sternberg Astronomical Institute of Moscow State University over seven nights, from June 23 to 30, 2024. Seeing estimates for altitudes greater than 500 m were inferred from scintillations in the sensor apertures separate from the total optical turbulence power. The zenith-adjusted seeing values were <span>(beta_{textrm{med}}approx 1overset{primeprime}{.}15)</span>, the corresponding seeing for the upper atmosphere was found to be of about <span>(0overset{primeprime}{.}28)</span>. A comparison of the seeing estimates obtained on these nights at telescopes with long exposures agrees well with the readings of the mobile differential image motion monitor. Some climatic parameters were also obtained both from a stationary weather station near the observation point and from satellite data.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 2","pages":"321 - 327"},"PeriodicalIF":1.4,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144888113","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":"Activity of G Dwarf HD 284521 (K2-370) and Atmospheric Losses of Its Exoplanet","authors":"I. S. Savanov","doi":"10.1134/S1990341325600115","DOIUrl":"10.1134/S1990341325600115","url":null,"abstract":"<p>An analysis of the activity evidence of the chromospherically active solar-type dwarf HD 284521, which has a sub-Neptune-type planet, is presented. Based on the data from the Kepler and TESS missions, the stellar rotation period was estimated (<span>(P_{textrm{rot}}=13{-}14)</span> days) and the evolution of cold spots on its surface was examined. Estimates of the areas of these spots were obtained, which, according to the data from the Kepler mission, equaled about 3.2<span>(%)</span> and, according to TESS observations, about 2.3, 1.2, 2.3, and 2.5<span>(%)</span> of its surface area. Based on the data from the long-term Kamogata Wide-field Survey (KWS) and data from the All Sky Automated Survey (ASAS) observation archive, the value of the star’s long-term activity cycle was found to be about 3800 days (10.4 yrs). The cycle length is comparable to that of the Sun, but HD 284521 rotates about twice as fast as the Sun. An analysis of measurements of the <span>(S)</span> index characterizing the chromospheric activity of the star also indicates the presence of a long-period variability. The results obtained from studying the stellar activity were used to estimate the loss of atmospheric matter from the planet HD 284521 b. An approximation formula corresponding to the energy-constrained atmospheric loss model was applied. Based on 135 estimates of the <span>(S)</span> parameter, the matter loss from the atmosphere of HD 284521 b over an interval of 1886 days (approximately five years) was calculated. The matter losses (<span>(log M_{textrm{loss}})</span>) of the atmosphere of the planet HD 284521 b are in the range of 9.8 to 10.3 with a median value of 10.2. The high amount of matter loss from the atmosphere of this planet is due to a significant flux of XUV photons caused by the high activity of the solar-type star. The study of the planetary system HD 284521 continues our series of studies of planetary systems, in which the central star is an analog of the Sun.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 2","pages":"235 - 241"},"PeriodicalIF":1.4,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144888115","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":"Studies of the Lagoon Nebula in the H({boldsymbol{alpha}}) Emission Line Using DEFPOS Spectrometer","authors":"M. Sahan","doi":"10.1134/S1990341324600480","DOIUrl":"10.1134/S1990341324600480","url":null,"abstract":"<p>DEFPOS Fabry–Perot spectrometer, located at the coude exit of the RTT-150 telescope (Bakirlitepe, Antalya, Turkey), has been used to measure the ionized gas within the Lagoon Nebula (M 8) which is an H II region (Sh2-25). Eighty-four H<span>(alpha)</span> emission line spectra obtained from the H II region provide detailed information about some physical properties of the gas surrounding the H II region. The line widths, <span>(V_{textrm{LSR}})</span> velocities, and <span>({I_{textrm{ H}{alpha}}})</span> intensities of the H<span>(alpha)</span> emission spectra were found to be in the range from <span>(27.5pm 5.80)</span> to <span>(41.50pm 1.99)</span> km s<span>({}^{-1})</span> (mean <span>(35.50pm 2.05)</span> km s<span>({}^{-1})</span>), <span>(-13.67pm 0.58)</span> and <span>(3.19pm 0.72)</span> km s<span>({}^{-1})</span> (mean <span>(-4.92pm 0.32)</span> km s<span>({}^{-1})</span>), and <span>(173.35pm 9.97)</span> R and <span>(13834.20pm 21.56)</span> R (mean <span>(2247.65pm 8.33)</span> R), respectively. The mean LSR velocity and line width of the nebula were also compared with previous works. Since there is not enough information on intensities and LSR velocities of such galactic sources with low angular size in the literature, we believe that DEFPOS spectrometer will provide a powerful tool for the study of the diffuse ionized gas, and these new results may have significant contributions to the literature.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 2","pages":"223 - 234"},"PeriodicalIF":1.4,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144888027","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":"Three SU UMa Type Dwarf Novae in the Period Gap and Its Vicinity: CRTS J000130+050624, 1RXS J003828.7+250920 and V452 Cas","authors":"A. A. Sosnovskij,&nbsp;E. P. Pavlenko","doi":"10.1134/S1990341325600267","DOIUrl":"10.1134/S1990341325600267","url":null,"abstract":"<p>The results of photometric observations of three SU UMa type cataclysmic variables in the quiescent state (<span>(18overset{textrm{m}}{.}3-20overset{textrm{m}}{.}5)</span>) are presented. It is shown that the objects have different ouburst amplitudes: <span>(5^{textrm{ m}})</span>—CRTS J000130+050624; <span>(3overset{textrm{m}}{.}7)</span>—1RXS J003828.7+250920 and <span>(2overset{textrm{m}}{.}5)</span>—V452 Cas. The orbital period was first discovered for CRTS J000130+050624—0.09055(19) days, V452 Cas—0.084898(2) days, and updated for 1RXS J003828.7+250920—0.09451123(5) days. Ephemeris have been determined for the light curve minima of these objects associated with the orbital period. Estimates of the mass ratio of the components are <span>(q=0.181(6))</span>, <span>(0.198(1))</span>, <span>(0.183(2))</span> for 1RXS J003828.7+250920, CRTS J000130+050624, and V452 Cas, respectively. It is shown that these dwarf novae are located in the vicinity of the theoretical short-period boundary of the period gap and are in good agreement with known empirical data.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 2","pages":"173 - 180"},"PeriodicalIF":1.4,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144888022","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}