Rong-Jia Yang

Hebei University

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

J. H. Qiao

Beijing University of Technology

Z. D. Zhang

Institute of High Energy Physics

Yaqian Wang

Hebei University

H-

H. -R. Bao

University of Chinese Academy of Sciences

L. S. Nie

Henan University

A. Zhemchugov

European Organization for Nuclear Research

Y. Y. Peng

Lanzhou University

Y. Y. Duan

Soochow University

X. B. Gao

Nanjing Normal University

X. T. Ma

Taiyuan University of Technology

Cooperative Institutions

Institute of High Energy Physics

1,035

Chinese Academy of Sciences

502

University of Chinese Academy of Sciences

486

COMSATS University Islamabad

277

University of Science and Technology of China

253

China Center of Advanced Science and Technology

235

Henan University

235

Inner Mongolia University

229

Centre National de la Recherche Scientifique

193

Central China Normal University

166

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

Newtonian Forms for Dilaton Spacetimes in String Theory

Chinese Physics Letters (2004)

Rong-Jia Yang Jiliang Jing

We show that the Newtonian forms for the motion of particles in mechanics and for light in geometrical optics can be extend to the Gibbons–Meada and the Garfinkle–Horne dilaton spacetimes in string theory. As an example, we study the bending of the light rays, the perihelion advance of a planet, and the radar echo delay in the dilaton spacetimes. The results show that the gravitational effects arising from the dilaton can be observed provided that the dilaton is large enough.

Dilaton

10.1088/0256-307x/21/3/046

Cite

Citations (0)

Possible evidences from H(z) parameter data for physics beyond ΛCDM

New Astronomy (2023)

Rong-Jia Yang

We analyse H(z) parameter data with some conditions by using Lagrange mean value theorem in Calculus. We find that: (1) there exists decelerated phase at 1 σ confidence level in the redshift range (0.38,0.59); (2) the equation of motion of dark energy may be less than −1 at 1 σ confidence level at some redshifts in the redshift range (1.3,1.53); (3) there exists accelerated phase at 1 σ confidence level in the redshift range (1.037,1.944). These results may provide possible evidences for physics beyond ΛCDM.

10.1016/j.newast.2023.102180

Cite

Citations (1)

Large-scale structure in superfluid Chaplygin gas cosmology

Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D, Particles, fields, gravitation, and cosmology (2014)

Rong-Jia Yang

We investigate the growth of large-scale structure in the superfluid Chaplygin gas (SCG) model. Both linear and non-linear growth, such as $\sigma_8$ and the skewness $S_3$, are discussed. We find the growth factor of SCG reduces to the EdS case at early times while differs from the $\Lambda$CDM case in the large $a$ limit. We also find there will be much stricture growth on large scales in the SCG scenario than in $\Lambda$CDM and the variations of $\sigma_{8}$ and $S_3$ between SCG and $\Lambda$CDM can not be discriminated.

Chaplygin gas

Sigma

Scale factor (cosmology)

10.1103/physrevd.89.063014

Cite

Citations (8)

Accretion onto a Moving Reissner-Nordstr\"{o}m or Kerr-Newman Black Hole

arXiv (Cornell University) (2016)

Lei Jiao Rong-Jia Yang

We obtain an analytic solution for accretion of a gaseous medium with a adiabatic equation of state ($P=\rho$) onto a Reissner-Nordstr\{o}m or Kerr-Newman black hole which moves at a constant velocity through the medium. We present the mass accretion rate which depends on the mass, the electric charge or the angular momentum. The flow is two dimensional for Reissner-Nordstr\{o}m black hole but is fully three dimensional for Kerr-Newman Black Hole.

Black hole (networking)

Source

Cite

Citations (0)

New types of f(T) gravity

The European Physical Journal C (2011)

Rong-Jia Yang

f(R) gravity

10.1140/epjc/s10052-011-1797-9

Cite

Citations (130)

Thin accretion disk around Kerr-Sen black hole in Einstein-Maxwell-dilaton-axion gravity

arXiv (Cornell University) (2024)

Haiyuan Feng Rong-Jia Yang

We investigate the accretion process in a thin disk surrounding a supermassive black hole in Einstein-Maxwell-dilaton-axion gravity by using the Novikov-Thorne model. Our exploration focuses on understanding the impact of the model parameter on various physical properties of the disk. The results reveal that as the dilaton parameter $r_2$ increases, the energy flux, radiation temperature, spectra luminosity, and conversion efficiency of the disk all increase. By narrowing down the dilaton parameter range to $0\leqslant r_2\leqslant0.4$ M, we discover that in the high-frequency region, the Kerr-Sen black hole demonstrates higher energy output compared to the Kerr black hole. This facilitates a more straightforward examination of the observational results for two black holes.

Black hole (networking)

Dilaton

Accretion disc

10.48550/arxiv.2403.18541

Cite

Citations (0)

New types of $f(T)$ gravities

arXiv (Cornell University) (2010)

Rong-Jia Yang

Source

Cite

Citations (7)

Low intensity beam current measurement of the Associated Proton Beam Line at CSNS

Journal of Physics Conference Series (2024)

Ruiyang Qiu Wei Huang Fei Li L. Zeng Muhammad Abdul Rehman

Abstract The Associated Proton beam Experiment Platform (APEP) beamline is the first proton irradiation facility to use naturally-stripped protons which come from H-beams interacting with the residual gas in the linac beampipe at CSNS. The stripped beam current, which is in the order of 0.1% of the original H-beam and approximately 10 μA, should be measured precisely to provide the proton number for irradiation experiments. Therefore, a low-intensity beam current measurement system was developed with considerations to eliminate the external interferences. An anti-interference design is adopted in this system with an elaboration of probes, cables and electronic low-noise technology to minimize the impact of environmental noise and interferences. This improves the signal-to-noise ratio and enables a more precise measurement of the microampere level pulsed beam current. The system was installed and tested during the summer maintenance in 2021 and 2022. It shows a good agreement with the measurement of the Faraday cup.

Faraday cup

Intensity

10.1088/1742-6596/2681/1/012001

Cite

Citations (1)

Age crisis in $\Lambda$CDM model?

Rong-Jia Yang Shuang‐Nan Zhang

The age problem in the $\Lambda$CDM model is re-examined. We define the elapsed time $T$ of an object is its age plus the age of the Universe when it was born. Therefore in any cosmology, $T$ must be smaller than the age of the Universe. For the old quasar APM 08279+5255 at $z=3.91$, previous studies have determined the best-fit value of $T$, 1 $\sigma$ lower limit and the lowest limit to $T$ are 2.3, 2.0 and 1.7 Gyr, respectively. Constrained from SNIa$+R+A+d$, SNIa$+R+A+d+H(z)$, and WMAP5+2dF+SNLS+HST+BBN, the $\Lambda$CDM model can only accommodate $T(z=3.91)=1.7$ Gyr at 1 $\sigma$ deviation. Constrained from WMAP5 results only, the $\Lambda$CDM model can only accommodate $T(z=3.91)=1.7$ Gyr at 2 $\sigma$ deviation. In all these cases, we found that $\Lambda$CDM model accommodates the total age (14 Gyr for $z=0$) of the Universe estimated from old globular clusters, but cannot accommodate statistically the 1 $\sigma$ lower limit to the best-fit age of APM~08279+5255 at $z=3.91$. These results imply that the $\Lambda$CDM model may suffer from an age problem.

Sigma

Source

Cite

Citations (0)

Modified clock inequalities and modified black hole lifetime

Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D, Particles, fields, gravitation, and cosmology (2009)

Rong-Jia Yang Shuang‐Nan Zhang

Based on a generalized uncertainty principle, Salecker-Wigner inequalities are modified. When applied to black holes, they give a modified black hole lifetime: ${T}_{\mathrm{MB}}\ensuremath{\sim}\frac{{M}^{3}}{{m}_{p}^{3}}(1\ensuremath{-}{m}_{p}^{2}/{M}^{2}){t}_{p}$, and the number of bits required to specify the information content of the black hole as the event horizon area in Planck units $N\ensuremath{\sim}\frac{{M}^{2}}{{m}_{p}^{2}}(1\ensuremath{-}{m}_{p}^{2}/{M}^{2})$.

Black hole (networking)

10.1103/physrevd.79.124005

Cite

Citations (10)