Revista Mexicana de Astronomia y Astrofisica最新文献

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LATE ACCELERATED EXPANSION OF THE UNIVERSE IN DIFFUSIVE SCENARIOS 在扩散情况下,宇宙的后期加速膨胀
4区 物理与天体物理
Revista Mexicana de Astronomia y Astrofisica Pub Date : 2023-10-01 DOI: 10.22201/ia.01851101p.2023.59.02.15
Eduard Fernando Piratova Moreno, Luz Ángela García
{"title":"LATE ACCELERATED EXPANSION OF THE UNIVERSE IN DIFFUSIVE SCENARIOS","authors":"Eduard Fernando Piratova Moreno, Luz Ángela García","doi":"10.22201/ia.01851101p.2023.59.02.15","DOIUrl":"https://doi.org/10.22201/ia.01851101p.2023.59.02.15","url":null,"abstract":"We present a diffusion model in a cosmological framework to describe the accelerated expansion of the Universe at late times. We first introduce a scalar field in Einstein's field equations to account for the effect of diffusion as the driver of today's expansion. We also study a second option for the diffusion source: a perfect fluid with a barotropic equation of state. We establish the equations that relate the fluid evolution with the cosmic budget and find analytical solutions of the field equations with different diffusion coeffcients: constant, redshift-dependent, and σ proportional to the Hubble parameter. Our main finding is that diffusive processes in the Universe are viable scenarios to effectively describe the expansion dynamics once the model's free parameters are gauged. The choice of the diffusion coeffcient and the equation of state of the cosmic fluid determines the solutions of the density fractions and the transition to an accelerated expansion of the Universe at present.","PeriodicalId":49602,"journal":{"name":"Revista Mexicana de Astronomia y Astrofisica","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136055237","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}
引用次数: 0
CALIBRATION OF 122 SENSL MICROFJ-60035 SIPMS AND THE REDUCTION OF OPTICAL CROSS-TALK DUE TO COUPLED LIGHT GUIDES 122传感器microfj-60035 sipms的校正及耦合光导引起的光串扰的减小
4区 物理与天体物理
Revista Mexicana de Astronomia y Astrofisica Pub Date : 2023-10-01 DOI: 10.22201/ia.01851101p.2023.59.02.14
F. Rehbein, T. Bretz, R. Alfaro, J. Audehm, A. Biland, G. Do, M. M. González, Y. F. Pérez-Araujo, M. Schaufel, J. Serna-Franco, I. Torres
{"title":"CALIBRATION OF 122 SENSL MICROFJ-60035 SIPMS AND THE REDUCTION OF OPTICAL CROSS-TALK DUE TO COUPLED LIGHT GUIDES","authors":"F. Rehbein, T. Bretz, R. Alfaro, J. Audehm, A. Biland, G. Do, M. M. González, Y. F. Pérez-Araujo, M. Schaufel, J. Serna-Franco, I. Torres","doi":"10.22201/ia.01851101p.2023.59.02.14","DOIUrl":"https://doi.org/10.22201/ia.01851101p.2023.59.02.14","url":null,"abstract":"The excellent production quality of recent generations of Silicon Photomultipliers (SiPMs) allows for operation without individual calibration of the breakdown voltage. Measurements of the crosstalk probability and the relative gain of 122 SiPMs of type SensL MicroFJ-60035-TSV are presented. Semi-conductor photo sensors have replaced photo multiplier tubes in numerous applications featuring single-photon resolution, insensitivity to magnetic fields, higher robustness and enhanced photo detection efficiency at lower operation voltage and lower costs. Light guides are used to increase the comparably small photo sensitive area of SiPMs. Their optical coupling changes the surface conditions of the sensor and influences the probability for crosstalk photons to leave the sensor without inducing secondary breakdowns. This study compares properties of sensors that are optically coupled to light guides with bare sensors, operated at nominal bias voltage. It demonstrates, that the optical coupling to a light guide significantly reduces the crosstalk probability of the measured sensors.","PeriodicalId":49602,"journal":{"name":"Revista Mexicana de Astronomia y Astrofisica","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136119580","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}
引用次数: 1
SEARCH AND STUDY OF ULTRACOMPACT H II REGIONS 超紧h区域的搜索与研究
4区 物理与天体物理
Revista Mexicana de Astronomia y Astrofisica Pub Date : 2023-10-01 DOI: 10.22201/ia.01851101p.2023.59.02.08
D. Quiroga-González, M. A. Trinidad, E. de la Fuente, J. M. Masqué, T. Rodríguez–Esnard
{"title":"SEARCH AND STUDY OF ULTRACOMPACT H II REGIONS","authors":"D. Quiroga-González, M. A. Trinidad, E. de la Fuente, J. M. Masqué, T. Rodríguez–Esnard","doi":"10.22201/ia.01851101p.2023.59.02.08","DOIUrl":"https://doi.org/10.22201/ia.01851101p.2023.59.02.08","url":null,"abstract":"We present results from a sample of 106 high-luminosity IRAS sources observed with the Very Large Array in the B and C configurations. 96 sources were observed in the X-band and 52 in the K-band, with 42 of them observed at both wavelengths. We also used previously published observations in the C-band for 14 of them. The detection rate of sources with 3.6 cm continuum emission was ≈ 25%, while only 10% have emission at 1.3 cm. In order to investigate the nature of these sources, their physical parameters were calculated mainly using the 3.6 cm continuum emission, and for sources detected at two wavelengths, we used the best fit of three H iiregion models with different geometries. As a final result, we present a catalog of the detected sources, which includes their basic physical parameters for further analysis. The catalog contains 17 ultracompact H II regions and 3 compact H II regions.","PeriodicalId":49602,"journal":{"name":"Revista Mexicana de Astronomia y Astrofisica","volume":"131 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136055246","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}
引用次数: 0
SOLAR-TYPE ECLIPSING BINARY KIC 4832197: PHYSICAL PROPERTIES AND INTRINSIC VARIABILITY OF THE COMPONENTS 日型食双星kic 4832197:组分的物理性质和内在变异性
4区 物理与天体物理
Revista Mexicana de Astronomia y Astrofisica Pub Date : 2023-10-01 DOI: 10.22201/ia.01851101p.2023.59.02.09
O. Özdarcan, H. A. Dal, E. Yoldaş
{"title":"SOLAR-TYPE ECLIPSING BINARY KIC 4832197: PHYSICAL PROPERTIES AND INTRINSIC VARIABILITY OF THE COMPONENTS","authors":"O. Özdarcan, H. A. Dal, E. Yoldaş","doi":"10.22201/ia.01851101p.2023.59.02.09","DOIUrl":"https://doi.org/10.22201/ia.01851101p.2023.59.02.09","url":null,"abstract":"Comprehensive analysis of optical spectroscopy and space photometry of the solar type eclipsing binary system KIC 4832197 is presented. The system is composed of F7V + F9V components with masses of M1 = 1.16 ± 0.12 M☉, M2 = 1.07 ± 0.10 M☉ and radii of R1 = 1.26 ± 0.04 R☉, R2 = 1.03 ± 0.03 R☉. The position of the components on the Log Teff – Log L/L☉ plane suggests an age of 2.8 ± 0.8 Gyr for the system. Inspection of out-of-eclipse brightness in time reveals a wave-like variability pattern, whose amplitude and shape quickly change on order of days. Frequency analysis of this variability results in two significant peaks in the amplitude spectrum, which are interpreted as rotational modulation of spots on the components. Assuming both spots are on the same component, a lower limit for the differential rotation coeffcient is computed as k = 0.12, which is weaker compared to the solar value of k☉ = 0.189.","PeriodicalId":49602,"journal":{"name":"Revista Mexicana de Astronomia y Astrofisica","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136055234","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}
引用次数: 0
SDSS-IV MANGA: THE RADIAL DISTRIBUTION OF PHYSICAL PROPERTIES WITHIN GALAXIES IN THE NEARBY UNIVERSE Sdss-iv漫画:附近宇宙中星系内物理性质的径向分布
4区 物理与天体物理
Revista Mexicana de Astronomia y Astrofisica Pub Date : 2023-09-01 DOI: 10.22201/ia.01851101p.2023.59.02.06
J. K. Barrera-Ballesteros, S. F. Sánchez, C. Espinosa-Ponce, C. López-Cobá, L. Carigi, A. Z. Lugo-Aranda, E. Lacerda, G. Bruzual, H. Hernandez-Toledo, N. Boardman, N. Drory, Richard R. Lane, J. R. Brownstein
{"title":"SDSS-IV MANGA: THE RADIAL DISTRIBUTION OF PHYSICAL PROPERTIES WITHIN GALAXIES IN THE NEARBY UNIVERSE","authors":"J. K. Barrera-Ballesteros, S. F. Sánchez, C. Espinosa-Ponce, C. López-Cobá, L. Carigi, A. Z. Lugo-Aranda, E. Lacerda, G. Bruzual, H. Hernandez-Toledo, N. Boardman, N. Drory, Richard R. Lane, J. R. Brownstein","doi":"10.22201/ia.01851101p.2023.59.02.06","DOIUrl":"https://doi.org/10.22201/ia.01851101p.2023.59.02.06","url":null,"abstract":"Using the largest sample of galaxies observed with an optical integral field unit (IFU, the SDSS-IV MaNGA survey, ≈10000 targets), we derive the radial distribution of the physical properties obtained from the stellar continuum and the ionized-gas emission lines. Given the large sample, we are able to explore the impact of the total stellar mass and morphology by averaging those radial distributions for different bins of both global properties. In general, we find that most of the properties exhibit a negative gradient, with a secondary impact by global properties. Our results confirm the intimate interplay between the properties of the stellar component and those of the ionized gas at local (kpc) scales to set the observed radial gradients. The resemblance of the gradients for similar global properties indicates statistical similar histories of star formation and chemical enrichment, with an initial radial gas distribution following the potential of the galaxy.","PeriodicalId":49602,"journal":{"name":"Revista Mexicana de Astronomia y Astrofisica","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135736327","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}
引用次数: 0
PHYSICAL PROPERTIES AND MEMBERSHIP DETERMINATION OF THE OPEN CLUSTERS IC 4665, NGC 6871 AND DZIM 5 THROUGH uvby - β PHOTOELECTRIC PHOTOMETRY 用uvby-β光电光度法测定疏散星团IC4665、NGC6871和DZIM5的物理性质和成员
IF 1 4区 物理与天体物理
Revista Mexicana de Astronomia y Astrofisica Pub Date : 2023-04-01 DOI: 10.22201/ia.01851101p.2023.59.01.03
J. Pena, A. Renterı́a, J. D. Paredes, D. S. Piña
{"title":"PHYSICAL PROPERTIES AND MEMBERSHIP DETERMINATION OF THE OPEN CLUSTERS IC 4665, NGC 6871 AND DZIM 5 THROUGH uvby - β PHOTOELECTRIC PHOTOMETRY","authors":"J. Pena, A. Renterı́a, J. D. Paredes, D. S. Piña","doi":"10.22201/ia.01851101p.2023.59.01.03","DOIUrl":"https://doi.org/10.22201/ia.01851101p.2023.59.01.03","url":null,"abstract":"uvby - β photoelectric photometry of stars in the direction of the open clusters IC 4665, NGC 6871 and Dzim 5 is presented. From this uvby - β photometry we classified the spectral types which allowed us to determine the reddening and, hence, the distance. Membership of the stars to the cluster was determined. Our results are compared with those obtained by GAIA DR2.","PeriodicalId":49602,"journal":{"name":"Revista Mexicana de Astronomia y Astrofisica","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47440601","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}
引用次数: 0
SOME PREDICTIONS OF SCALING RELATIONS: THE CASE OF THE BLACK HOLE IN M87 标度关系的一些预测:M87黑洞的情况
IF 1 4区 物理与天体物理
Revista Mexicana de Astronomia y Astrofisica Pub Date : 2023-04-01 DOI: 10.22201/ia.01851101p.2023.59.01.06
A. L. Iannella, A. Feoli
{"title":"SOME PREDICTIONS OF SCALING RELATIONS: THE CASE OF THE BLACK HOLE IN M87","authors":"A. L. Iannella, A. Feoli","doi":"10.22201/ia.01851101p.2023.59.01.06","DOIUrl":"https://doi.org/10.22201/ia.01851101p.2023.59.01.06","url":null,"abstract":"In the context of supermassive black holes and their host galaxies, we consider two scaling relations: M• - Reσ3 and M• - MGσ2, to derive three fundamental parameters for the supermassive black hole at the center of M87. In this paper we will get predictions for the efficiency and mass of the black hole, and the temperature of its accretion disk, by comparing them with the respective experimental values.","PeriodicalId":49602,"journal":{"name":"Revista Mexicana de Astronomia y Astrofisica","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45984974","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}
引用次数: 0
OPTIMAL TWO-IMPULSE INTERPLANETARY TRAJECTORIES: EARTH-VENUS AND EARTH-MARS MISSIONS 最佳双脉冲行星际轨迹:地球-金星和地球-火星任务
IF 1 4区 物理与天体物理
Revista Mexicana de Astronomia y Astrofisica Pub Date : 2023-04-01 DOI: 10.22201/ia.01851101p.2023.59.01.02
L. A. Gagg Filho, S. da Silva Fernandes, S. Villanova
{"title":"OPTIMAL TWO-IMPULSE INTERPLANETARY TRAJECTORIES: EARTH-VENUS AND EARTH-MARS MISSIONS","authors":"L. A. Gagg Filho, S. da Silva Fernandes, S. Villanova","doi":"10.22201/ia.01851101p.2023.59.01.02","DOIUrl":"https://doi.org/10.22201/ia.01851101p.2023.59.01.02","url":null,"abstract":"This work describes several models to design optimal interplanetary trajectories. The transfer problem consists in transferring a space vehicle from a circular low Earth orbit (LEO) to a circular low orbit around a destiny planet (Venus or Mars). Models based on the two-body, four-body, and five-body problems are considered. Also, several versions of the patched-conic approximation are utilized including a detailed version that designs a lunar swing-by maneuver. The results show that the optimal trajectories for Earth-Mars and Earth-Venus missions collide with the Moon if a lunar swing-by maneuver with an unspecified altitude of the closest approach is included in the trajectory design; however, sub-optimal trajectories that do not collide with the Moon exist, presenting a smaller fuel consumption than the trajectories without lunar swing-by and with no greater changes in the time of flight.","PeriodicalId":49602,"journal":{"name":"Revista Mexicana de Astronomia y Astrofisica","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44808012","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}
引用次数: 0
PHOTOMETRIC OBSERVATIONS OF MINOR PLANETS WITH THE TONANTZINTLA SCHMIDT CAMERA I. LIGHT CURVE ANALYSIS OF MAIN-BELT AND NEAR-EARTH ASTEROIDS 用tonantzintla schmidt照相机观测小行星的光度。主带和近地小行星的光曲线分析
IF 1 4区 物理与天体物理
Revista Mexicana de Astronomia y Astrofisica Pub Date : 2023-04-01 DOI: 10.22201/ia.01851101p.2023.59.01.04
J. Valdes, R. Mújica, J. Guichard, S. Camacho, G. Cerdán, J. Michimani, R. Vega
{"title":"PHOTOMETRIC OBSERVATIONS OF MINOR PLANETS WITH THE TONANTZINTLA SCHMIDT CAMERA I. LIGHT CURVE ANALYSIS OF MAIN-BELT AND NEAR-EARTH ASTEROIDS","authors":"J. Valdes, R. Mújica, J. Guichard, S. Camacho, G. Cerdán, J. Michimani, R. Vega","doi":"10.22201/ia.01851101p.2023.59.01.04","DOIUrl":"https://doi.org/10.22201/ia.01851101p.2023.59.01.04","url":null,"abstract":"We report photometric observations of nine main-belt asteroids (MBAs), four near-Earth asteroids (NEAs), and one Mars-crossing asteroid (MCA) carried out with the historical Tonantzintla Schmidt Camera between 2015 and 2018, as part of a process of reactivation of this telescope for astrometric and photometric follow-up observations of MBAs and NEAs. This observational program is part of the commitment made by INAOE when requesting its inclusion in the International Asteroid Warning Network (IAWN). We present the light curves of these 14 asteroids and their corresponding Fourier analyses to determine the rotation period of the asteroids and the brightness amplitude of their light curves.","PeriodicalId":49602,"journal":{"name":"Revista Mexicana de Astronomia y Astrofisica","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47653004","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}
引用次数: 0
REFRACTION OF A HERBIG-HARO JET TRAVELLING THROUGH A SHEAR LAYER HERBIG-HARO射流在剪切层中的折射
IF 1 4区 物理与天体物理
Revista Mexicana de Astronomia y Astrofisica Pub Date : 2023-04-01 DOI: 10.22201/ia.01851101p.2023.59.01.07
A. Raga, A. Castellanos-Ramírez, J. Cantó
{"title":"REFRACTION OF A HERBIG-HARO JET TRAVELLING THROUGH A SHEAR LAYER","authors":"A. Raga, A. Castellanos-Ramírez, J. Cantó","doi":"10.22201/ia.01851101p.2023.59.01.07","DOIUrl":"https://doi.org/10.22201/ia.01851101p.2023.59.01.07","url":null,"abstract":"We study the problem of a radiative Herbig-Haro (HH) jet which travels through a slip surface into a region of side-streaming environment. The interaction with the streaming environment produces an oblique shock that deflects the jet beam. A simple, analytic model for this shock gives the jet deflection as a function of the incidence angle and the environment-to-jet ram pressure ratio. We find that in the case of higher environmental ram pressure, for a high enough incidence angle, the jet stalls and does not penetrate substantially into the streaming environment. We present 3D gas dynamic simulations illustrating the jet deflection and stalling regimes. Possible applications to HH jets showing sudden deflections in their propagation are discussed.","PeriodicalId":49602,"journal":{"name":"Revista Mexicana de Astronomia y Astrofisica","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46948608","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}
引用次数: 0
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