Evolution of velocity dispersion along cold collisionless flows

Banik, Nilanjan; Sikivie, Pierre

doi:10.1103/PhysRevD.93.103509

Title: Evolution of velocity dispersion along cold collisionless flows

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Abstract

We found that the infall of cold dark matter onto a galaxy produces cold collisionless flows and caustics in its halo. If a signal is found in the cavity detector of dark matter axions, the flows will be readily apparent as peaks in the energy spectrum of photons from axion conversion, allowing the densities, velocity vectors and velocity dispersions of the flows to be determined. We also discuss the evolution of velocity dispersion along cold collisionless flows in one and two dimensions. A technique is presented for obtaining the leading behaviour of the velocity dispersion near caustics. The results are used to derive an upper limit on the energy dispersion of the Big Flow from the sharpness of its nearby caustic, and a prediction for the dispersions in its velocity components.

Authors:

Banik, Nilanjan ^[1]; Sikivie, Pierre ^[2]

Univ. of Florida, Gainesville, FL (United States); Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Univ. of Florida, Gainesville, FL (United States)

Publication Date:: Sun May 01 00:00:00 EDT 2016

Research Org.:: Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

Sponsoring Org.:: USDOE Office of Science (SC), High Energy Physics (HEP)

OSTI Identifier:: 1230048

Alternate Identifier(s):: OSTI ID: 1252382

Report Number(s):: FERMILAB-PUB-15-480-A-AE-PPD
Journal ID: ISSN 2470-0010; PRVDAQ; arXiv eprint number arXiv:1511.05947; TRN: US1601631

Grant/Contract Number:: AC02-07CH11359; FG02-97ER41209

Resource Type:: Accepted Manuscript

Journal Name:: Physical Review D

Additional Journal Information:: Journal Volume: 93; Journal Issue: 10; Journal ID: ISSN 2470-0010

Publisher:: American Physical Society (APS)

Country of Publication:: United States

Language:: English

Subject:: 79 ASTRONOMY AND ASTROPHYSICS

Citation Formats


                    Banik, Nilanjan, and Sikivie, Pierre. Evolution of velocity dispersion along cold collisionless flows.  United States: N. p., 2016. 
Web.  doi:10.1103/PhysRevD.93.103509.

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                    Banik, Nilanjan, & Sikivie, Pierre. Evolution of velocity dispersion along cold collisionless flows.  United States.  https://doi.org/10.1103/PhysRevD.93.103509

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                    Banik, Nilanjan, and Sikivie, Pierre. Sun .  
"Evolution of velocity dispersion along cold collisionless flows".  United States.  https://doi.org/10.1103/PhysRevD.93.103509.  https://www.osti.gov/servlets/purl/1230048.

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@article{osti_1230048,

  title        = {Evolution of velocity dispersion along cold collisionless flows},

  author       = {Banik, Nilanjan and Sikivie, Pierre},

  abstractNote = {We found that the infall of cold dark matter onto a galaxy produces cold collisionless flows and caustics in its halo. If a signal is found in the cavity detector of dark matter axions, the flows will be readily apparent as peaks in the energy spectrum of photons from axion conversion, allowing the densities, velocity vectors and velocity dispersions of the flows to be determined. We also discuss the evolution of velocity dispersion along cold collisionless flows in one and two dimensions. A technique is presented for obtaining the leading behaviour of the velocity dispersion near caustics. The results are used to derive an upper limit on the energy dispersion of the Big Flow from the sharpness of its nearby caustic, and a prediction for the dispersions in its velocity components.},

  doi          = {10.1103/PhysRevD.93.103509},

  journal      = {Physical Review D},

  number       = 10,

  volume       = 93,

  place        = {United States},

  year         = {Sun May 01 00:00:00 EDT 2016},

  month        = {Sun May 01 00:00:00 EDT 2016}

}

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