UBV photometry of RT Persei     

B. B. Sanwal  U. S. Chaubey 《Astrophysics and Space Science》1981,75(2):329-340

Photoelectric and absolute elements of the system RT Per have been determined inU, B, andV filters. It is suggested that the primary star may be surrounded by a gaseous disk.  相似文献   

Period study of the binary star SW Cygni     

U. S. Chaubey 《Astrophysics and Space Science》1980,67(1):129-135

The O−C curve of SW Cyg between 1880 and 1977 is presented and discussed. It is found that the orbital period undergoes a systematic change, becoming greater with time. In addition, a periodic oscillation of amplitude 0 _. ^d 015 with period of 43.8 years is superimposed on this general trend. It is concluded that the increase in the period is due to a transfer of mass from the secondary star to the primary and the periodic oscillation is due to the light time effect of the third body of mass functionf(m)=0.006M _⊙.  相似文献   

Photometric elements and evolutionary status of eclipsing binary DI Pegasi     

U. S. Chaubey 《Astrophysics and Space Science》1982,81(1-2):283-293

The light curves of eclipsing binary DI Pegasi inU, B. andV filters have been presented and discussed. Photometric elements of the system have been determined. Using the colour indices, we estimate absolute dimensions and discuss the evolutionary status of the system.  相似文献   

Bianchi type-V bulk viscous cosmological models with particle creation in Brans-Dicke theory     

R. Chaubey 《Astrophysics and Space Science》2012,342(2):499-509

The Bianchi type-V cosmological model with viscous fluid and creation particle in Brans-Dicke theory has been considered. The present paper deals with Bianchi type-V cosmological model with bulk viscosity and particle creation described by full causal thermodynamics in Brans-Dicke theory. We have discussed two types of solutions of the average scale factor for a Bianchi type-V model by using a variation law of Hubble’s parameter, which yields a constant value of the deceleration parameter. The exact solutions to the corresponding field equations are obtained in quadrature form. The solutions to the Einstein field equations are obtained for power law and exponential form. The cosmological parameters have been discussed in detail.  相似文献   

Uncertainty of hydrologic simulation,and its impact on the design and the effectiveness of water conservation structures     

Vema  Vamsi Krishna  Sudheer  K. P.  Chaubey  I. 《Stochastic Environmental Research and Risk Assessment (SERRA)》2020,34(7):973-991

Stochastic Environmental Research and Risk Assessment - The uncertainties associated with the simulation models are often ignored in operational hydrology. While many methods are available for...  相似文献   

Depth anomalies in the Arabian Basin, NW Indian Ocean     

K. K. Ajay  A. K. Chaubey 《Geo-Marine Letters》2008,28(1):15-22

We present previously unreported depth anomalies in the Arabian Basin, northwest Indian Ocean, to provide constraints on the evolution of the oceanic lithosphere of that basin. The depth anomaly reported in this study was calculated as the difference between the observed depth to oceanic basement (corrected for sediment load) and the calculated depth to oceanic basement of the same age. The results indicate an anomalous depth to basement of oceanic crust in the Arabian Basin in the age bracket of 63–42 Ma, suggesting that subsidence in this basin does not follow the age–depth relationship of normal oceanic crust. The depth anomalies in the basin vary from +501 to −905 m. A negative depth anomaly zone, mapped in the eastern part of the basin near the Laccadive Ridge, indicates that here the basement depth is shallower than predicted. By contrast, a positive depth anomaly zone, mapped in the western part of the basin, indicates a deeper basement depth than expected. We propose that the excess subsidence of basement of the western part of the basin is probably caused by a relatively cold mantle, compared to the nearby eastern part of the basin which is affected by the intense thermal field of the former Reunion hotspot. Here, the rise in oceanic basement is caused by the vertical upwelling of oceanic crust due to convection, followed by a lateral across-axis flow facilitated by the Reunion hotspot at the time of spreading in early Tertiary times. This interpretation is in good agreement with spreading-ridge propagation and ridge-hotspot interaction reported earlier for the basin.  相似文献   

Photometric elements of V364 cassiopeiae     

U. S. Chaubey 《Astrophysics and Space Science》1984,106(2):273-282

TheUBV photometric observations of the eclipsing binary V364 Cas have been discussed. Two sets of photometric elements, one based on the Russell and Merrill methods and the other based on Kopal's new method of the analysis of the light curves of eclipsing binary stars in the frequency-domain, have been derived. Using the observed colour indicesU-B andB-V, the spectral types of the systemic components are estimated. An examination of all the available times of minimum light of V364 Cas does not reveal any change in its orbital period.  相似文献   

The general class of Bianchi cosmological models with varying EoS parameter     

R. Chaubey  A. K. Shukla 《Astrophysics and Space Science》2015,356(1):181-193

  相似文献   

Loss of orbital angular momentum in close binary systems during their evolution     

U. S. Chaubey 《Astrophysics and Space Science》1979,64(1):177-182

A total 91 binary systems of systemic mass less than 6.5M have been studied. It is found that binary systems obey the relation: logH=C–1.8 logM whereC is constant having values –1.18, –2.12 and –2.27 respectively for detached, semi-detached and contact binary systems. It is inferred that during evolution, the systemic orbital angular momentum decreases.  相似文献   

Spectrophotometry of comet West (1975n) after the perihelion passage     

U. S. Chaubey 《Astrophysics and Space Science》1978,54(1):233-237

In the wavelength range 350 to 650 nm, the flux distribution of comet West (1975n) is presented for various dates following perihelion passage. The variations with heliocentric distance, in the flux of the emission features of the CN band at 388 nm, the C₂ bands at 474 nm, 516 nm and 563 nm and Na at 589 nm, have been discussed. It is concluded that the comet was dust rich.  相似文献