Mass formula

About: Mass formula is a research topic. Over the lifetime, 1248 publications have been published within this topic receiving 22043 citations.

Mass Formula of a Five-dimensional Almost-BPS Supergravity Soliton with a Magnetic "Bolt"

Abstract: We derive the Smarr formula for a five-dimensional spacetime which has a magnetic “bolt” in its center and is asymptotically R 1,3 ×S 1 . Supersymmetry – and so the BPS-bound – is broken by the holonomy. We show how each topological feature of a space-like hypersurface enters the mass formula and which ones in particular give rise to the violation of the BPS-bound.

Ultra-spinning Chow’s black holes in six-dimensional gauged supergravity and their properties

Abstract: By taking the ultra-spinning limit as a simple solution-generating trick, a novel class of ultra-spinning charged black hole solutions has been constructed from Chow’s rotating charged black hole with two equal-charge parameters in six-dimensional $$ \mathcal{N} $$ = 4 gauged supergravity theory. We investigate their thermodynamical properties and then demonstrate that all thermodynamical quantities completely obey both the differential first law and the Bekenstein-Smarr mass formula. For the six-dimensional ultra-spinning Chow’s black hole with only one rotation parameter, we show that it does not always obey the reverse isoperimetric inequality, thus it can be either sub-entropic or super-entropic, depending upon the ranges of the mass parameter and especially the charge parameter. This property is obviously different from that of the six-dimensional singly-rotating Kerr-AdS super-entropic black hole, which always strictly violates the RII. For the six-dimensional doubly-rotating Chow’s black hole but ultra-spinning only along one spatial axis, we point out that it may also obey or violate the RII, and can be either super-entropic or sub-entropic in general.

New semi-empirical formulae for the binding and separation energies of single $\Lambda$ hypernuclei

Abstract: A new extended Bethe-Weizsacker mass formula (BWMF) is proposed for finding the binding energies of single $\Lambda$ hypernuclei. The binding energies calculated with the new formula agree well with the values calculated using other formulae. The binding energy per baryon (BE/A) for 71 predicted $\Lambda$ hypernuclei are evaluated using the new extended BWMF and are compared with RMF and SHF calculations. For calculating the $\Lambda$ separation energy, a new semi-empirical formula with standard deviation ( $\sigma = 0.6191$ ) is suggested. The values obtained with the formula proposed by us are in better agreement with the experimental $\Lambda$ separation energy than the values with other existing formalisms. We hope that our studies regarding the binding energies and separation energies of $\Lambda$ hypernuclei will be very helpful in future studies in this field.