10 research outputs found

    Mass of the black hole in the Seyfert 1.5 galaxy H 0507+164 from reverberation mapping

    Full text link
    We present the results of our optical monitoring campaign of the X-ray source H 0507+164, a low luminosity Seyfert 1.5 galaxy at a redshift z = 0.018. Spectroscopic observations were carried out during 22 nights in 2007, from the 21 of November to the 26 of December. Photometric observations in the R-band for 13 nights were also obtained during the same period. The continuum and broad line fluxes of the galaxy were found to vary during our monitoring period. The R-band differential light curve with respect to a companion star also shows a similar variability. Using cross correlation analysis, we estimated a time delay of 3.01 days (in the rest frame), of the response of the broad H-beta line fluxes to the variations in the optical continuum at 5100 angstroms. Using this time delay and the width of the H-beta line, we estimated the radius for the Broad Line Region (BLR) of 2.53 x 10^{-3} parsec, and a black hole mass of 9.62 x 10^{6} solar mass.Comment: 7 pages, 8 figures, Accepted for publication in MNRA

    Mass of the black hole in the Seyfert 1.5 galaxy H 0507+164 from reverberation mapping

    Get PDF
    We present the results of our optical monitoring campaign of the X-ray source H 0507+164, a low-luminosity Seyfert 1.5 galaxy at a redshift z= 0.018. Spectroscopic observations were carried out during 22 nights in 2007, from 2007 November 21 to 2007 December 26. Photometric observations in the R band for 13 nights were also obtained during the same period. The continuum and broad-line fluxes of the galaxy were found to vary during our monitoring period. The R-band differential light curve with respect to a companion star also shows a similar variability. Using cross-correlation analysis, we estimated a time-delay of τcen= 3.01+0.42− 1.84 d (in the rest frame) of the response of the broad Hβ line fluxes to the variations in the optical continuum at 5100 Å. Using this time-delay and the width of the Hβ line, we estimated the radius for the broad-line region of 2.53+0.35− 1.55× 10−3 pc and a black hole mass of 9.62+0.33− 3.73× 106 M

    Study on biology of Thryssa dussumieri (Valenciennes, 1848) from the coast of Ratnagiri, Maharashtra, India

    Get PDF
    The Dussumier’s thryssa, Thryssa dussumieri is one of the important component of by-catch of trawl and mini purse seine landings at Ratnagiri. The length-weight relationship indicated the isometric growth in T. dussumieri with generalized equation W = 0.0066 L 3.1077. The month-wise relative condition factor showed two peaks coinciding with peak spawning season. All morphometric lengths showed varying degree of correlation with total length. The qualitative and quantitative analysis of food revealed Thryssa dussumieri to be a carnivore, feeding mainly on mysids, copepods, diatoms and juvenile shrimps.The highest GSI value, for females, was observed during March, October, December and January. The male:female ratio was found to be 1:1.4. T. dussumieri has got a prolonged spawning season extending from September to April. The absolute fecundity ranged from 3367 to 14130 eggs with an average of 7420 eggs. Length at sexual maturity has been estimated to be 12.8 cm

    A seven square degrees survey for galaxy-scale gravitational lenses with the HST imaging archive

    Full text link
    We present the results of a visual search for galaxy-scale gravitational lenses in nearly 7 square degrees of Hubble Space Telescope (HST) images. The dataset comprises the whole imaging data ever taken with the Advanced Camera for Surveys (ACS) in the filter F814W (I-band) up to August 31st, 2011, i.e. 6.03 square degrees excluding the field of the Cosmic Evolution Survey (COSMOS) which has been the subject of a separate visual search. In addition, we have searched for lenses in the whole Wide Field Camera 3 (WFC3) near-IR imaging dataset in all filters (1.01 square degrees) up to the same date. Our primary goal is to provide a sample of lenses with a broad range of different morphologies and lens-source brightness contrast in order estimate a lower limit to the number of galaxy-scale strong lenses in the future Euclid survey in its VIS band. Our criteria to select lenses are purely morphological as we do not use any colour or redshift information.The final candidate selection is very conservative hence leading to a nearly pure but incomplete sample. We find 49 new lens candidates: 40 in the ACS images and 9 in the WFC3 images. Out of these, 16 candidates are secure lenses owing to their striking morphology, 21 more are very good candidates, and 12 more have morphologies compatible with gravitational lensing but also compatible with other astrophysical objects. It is therefore insensitive to cosmic variance and allows to estimate the number of galaxy-scale strong lenses on the sky for a putative survey depth, which is the main result of the present work. Because of the incompleteness of the sample, the estimated lensing rates should be taken as lower limits. Using these, we anticipate that a 15 000 square degrees space survey such as Euclid will find at least 60 000 galaxy-scale strong lenses down to a limiting AB magnitude of I = 24.5 (10-sigma) or I = 25.8 (3-sigma).Comment: 13 pages, 12 figures, Accepted for publication in MNRA

    Human Body Monitoring System Using Wsn With Gsm Andgps

    Full text link
    The main aim of our paper is to monitor and analyze the human body temperature, blood pressure (BP), Pulse Rate and ECG and tracking the patient location. The human body temperature, BP, Pulse Rate and ECG are detected and can be sensed by using respective sensors. The sensed information is send to the PIC18F4520 microcontroller through signal conditioning circuit in the patient unit. A desired amount of sensor value is set and if it is exceeded preliminary steps should be taken by the indicating by buzzer. The sensor information will be transmitted from the patient unit to the main controller unit with the help of GSM communication system which is connected with the microcontrollers in the both units. The main controller unit will send those sensed data as well as the location of that patient with the help of GPS Module to the observer [1]. The observer can receive the SMS sent by GSM module and further decision can be taken. The message is sent to a mobile phone using Global system mobile (GSM) Modem. MAX232 was a driver between microcontroller and modem

    Reproductive biology and fishery of the white sardine, <em>Escualosa thoracata</em> (Valenciennes, 1847) from the Ratnagiri coast, Maharashtra

    Get PDF
    2485-2491In the present study of this fish, it has indicated prolonged spawning season from October to April with peak spawning from November to February along the coast of Ratnagiri, Maharashtra. Highest GSI value for both sexes were observed during November (9.1487 for males and 5.4335 for females) and lowest during June (1.2772 for males and 0.8855 for females). The highest value of K was found in February for both sexes, male (2.06) and (1.86) in females. Overall male: female ratio was 1: 1.19 indicating slight dominance of females. The ova diameter for this species ranged from 0.02 to 0.64 mm, absolute fecundity ranged from 6156 to 9924 ova with an average of 7674 ova. Size at first maturity for females has been estimated to be 79 mm

    Preliminary observation on the sustainability of white sardine, Escualosa thoracata (Valenciennes, 1847), exploited from the central west coast of India

    No full text
    Background: The present study assessed the growth and mortality parameters of the white sardine, Escualosa thoracata which is having high local demand. The white sardine gained importance due to its taste, and high demand in domestic markets as compared to the oil sardine necessitated a study on this resource to know the present status of exploitation level along the central west coast of India. Results: A total of 3026 individuals of different size groups of E. thoracata were randomly collected from the Burondi fish landing center of the Ratnagiri district of Maharashtra. The asymptotic length (L∞) and growth coefficient (K) were estimated to be 115 mm and 1.9 year−1, respectively, by ELEFAN-I and 135 mm and 1.2 year−1 by the scattergram. The value of t0 by von Bertalanffy plot was estimated to be −0.000012 year. The fish attained a length of 65 mm, 94 mm, and 114 mm at the end of 0.5, 1, and 1.5 years of its life, respectively. The instantaneous rate of total mortality (Z), natural mortality (M), and fishing mortality (F) were estimated to be 8.07 year−1, 2.55 year−1, and 5.52 year−1, respectively. The exploitation rate (U) was calculated as 0.65, and the exploitation ratio (E) was 0.68. Conclusion: The growth, mortality, and other population parameters observed in the present study will help to understand the current stock status, which is pointing toward the over-fishing condition (E ˃ 0.50) of the white sardine in the study area. Therefore, the present investigation suggests reducing the fishing pressure on E. thoracata along the central west coast of India for the sustainability of the resource
    corecore