skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Separating the Universe into real and fake energy densities

; ; ;
Publication Date:
Sponsoring Org.:
OSTI Identifier:
Grant/Contract Number:
FG02-13ER41958; SC0009924
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review D
Additional Journal Information:
Journal Volume: 94; Journal Issue: 2; Related Information: CHORUS Timestamp: 2017-04-05 15:01:34; Journal ID: ISSN 2470-0010
American Physical Society
Country of Publication:
United States

Citation Formats

Hu, Wayne, Chiang, Chi-Ting, Li, Yin, and LoVerde, Marilena. Separating the Universe into real and fake energy densities. United States: N. p., 2016. Web. doi:10.1103/PhysRevD.94.023002.
Hu, Wayne, Chiang, Chi-Ting, Li, Yin, & LoVerde, Marilena. Separating the Universe into real and fake energy densities. United States. doi:10.1103/PhysRevD.94.023002.
Hu, Wayne, Chiang, Chi-Ting, Li, Yin, and LoVerde, Marilena. 2016. "Separating the Universe into real and fake energy densities". United States. doi:10.1103/PhysRevD.94.023002.
title = {Separating the Universe into real and fake energy densities},
author = {Hu, Wayne and Chiang, Chi-Ting and Li, Yin and LoVerde, Marilena},
abstractNote = {},
doi = {10.1103/PhysRevD.94.023002},
journal = {Physical Review D},
number = 2,
volume = 94,
place = {United States},
year = 2016,
month = 7

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1103/PhysRevD.94.023002

Citation Metrics:
Cited by: 3works
Citation information provided by
Web of Science

Save / Share:
  • The mean free path for direct electron pair production by electrons has been measured in the energy region 2 to 8, 8 to 32, and 32 to 150 Bev. The obtained values are less than those foreseen by Bhabha's theory. The disagreement is not imputable to energy underestimations. A three dimensional model of track formation in nuclear emulsion which accounts for the ionization variation observed at the beginning of electron pairs of more than ten Bev is described. This indicates that energy determinations using methods described in a previous paper are correct while energies evaluated on the basis of dipolemore » effect theory can be overestimated by l00 times. The number of unresolvable bremsstrahlung pairs produced on the track of an electron of known path and energy hns been calculated. Errors inherent to Koshiba and Kaplon's method are thus eliminated. (auth)« less
  • Flavor ratios of very high energy astrophysical neutrinos, which can be studied at the Earth by a neutrino telescope such as IceCube, can serve to diagnose their production mechanism at the astrophysical source. The flavor ratios for neutrinos and antineutrinos can be quite different as we do not know how they are produced in the astrophysical environment. Due to this uncertainty the neutrino and antineutrino flavor ratios at the Earth also could be quite different. Nonetheless, it is generally assumed that flavor ratios for neutrinos and antineutrinos are the same at the Earth, in fitting the high energy astrophysical neutrinomore » data. This is a reasonable assumption for the limited statistics for the data we currently have. However, in the future the fit must be performed allowing for a possible discrepancy in these two fractions in order to be able to disentangle different production mechanisms at the source from new physics in the neutrino sector. To reinforce this issue, in this work we show that a wrong assumption about the distribution of neutrino flavor ratios at the Earth may indeed lead to misleading interpretations of IceCube results.« less
  • A new method, which reduces the time required for carrying out float-sink analysis, requires that the coal sample be split to provide individual representative samples for each heavy liquid separation. Using a rotary sample splitter and adequate care, an accurate split of the sample can be made to meet the ASTM Standard D-2234.
  • Petrosian radii, effective radii, apparent magnitudes, and average surface brightnesses are presented for the first few ranked galaxies in 56 nearby clusters and groups. The correlations between (SB) and both M and R are derived from the data, and a selection effect that imitates a Tolman signal in these data but which is an artifact of the sample is discussed. Correction procedures are applied to the high-redshift galaxy sample of Djorgovski and Spinrad (1981),C and a well-defined Tolman signal is found in the data. Although this appears to be strong proof that the universe expands and therefore that the conventionalmore » interpretation of the redshift is correct, the reliability of the conclusion is cautioned. Methods to optimize the Tolman test in future observational programs are discussed. 66 refs.« less