Can one measure the Cosmic Neutrino Background?

The Cosmic Microwave Background (CMB) yields information about our Universe at around 380,000 years after the Big Bang (BB). Due to the weak interaction of the neutrinos with matter, the Cosmic Neutrino Background (CNB) should give information about a much earlier time of our Universe, around one second after the BB. Probably, the most promising method to “see” the CNB is the capture of the electron neutrinos from the Background by Tritium, which then decays into 3He and an electron with the energy of the the [Formula: see text]-value [Formula: see text] 18.562[Formula: see text]keV plus the electron neutrino rest mass. The “KArlsruhe TRItium Neutrino” (KATRIN) experiment, which is in preparation, seems presently the most sensitive proposed method for measuring the electron antineutrino mass. At the same time, KATRIN can also look by the reaction [Formula: see text]. The capture of the Cosmic Background Neutrinos (CNB) should show in the electron spectrum as a peak by the electron neutrino rest mass above [Formula: see text]. Here, the possibility to see the CNB with KATRIN is studied. A detection of the CNB by KATRIN seems not to be possible at the moment. But KATRIN should be able to determine an upper limit for the local electron neutrino density of the CNB.

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Cosmic Neutrino Background Limits at the KATRIN Experiment and Beyond

Nuclear Physics B - Proceedings Supplements ◽

10.1016/j.nuclphysbps.2012.09.113 ◽

2012 ◽

Vol 229-232 ◽

pp. 476

Author(s):

A.C. Kaboth ◽

J.A. Formaggio ◽

B. Monreal

Keyword(s):

Cosmic Neutrino Background ◽

Cosmic Neutrino ◽

Katrin Experiment ◽

Neutrino Background

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Detection prospects of the cosmic neutrino background

International Journal of Modern Physics A ◽

10.1142/s0217751x15300318 ◽

2015 ◽

Vol 30 (12) ◽

pp. 1530031 ◽

Cited By ~ 5

Author(s):

Yu-Feng Li

Keyword(s):

Direct Detection ◽

High Energy ◽

Big Bang ◽

Observational Evidence ◽

Future Prospects ◽

Cosmic Neutrino Background ◽

Cosmic Neutrino ◽

Massive Neutrinos ◽

Neutrino Background ◽

Excitation Method

The existence of the cosmic neutrino background (CνB) is a fundamental prediction of the standard Big Bang cosmology. Although current cosmological probes provide indirect observational evidence, the direct detection of the CνB in a laboratory experiment is a great challenge to the present experimental techniques. We discuss the future prospects for the direct detection of the CνB, with the emphasis on the method of captures on beta-decaying nuclei and the PTOLEMY project. Other possibilities using the electron-capture (EC) decaying nuclei, the annihilation of extremely high-energy cosmic neutrinos (EHECνs) at the Z-resonance, and the atomic de-excitation method are also discussed in this review (talk given at the International Conference on Massive Neutrinos, Singapore, 9–13 February 2015).

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THE DARK-MATTER WORLD: ARE THERE DARK-MATTER GALAXIES?

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512005703 ◽

2012 ◽

Vol 10 ◽

pp. 1-12

Author(s):

W-Y. PAUCHY HWANG

Keyword(s):

Dark Matter ◽

Time Span ◽

Neutrino Masses ◽

Ordinary Matter ◽

Cosmic Neutrino Background ◽

Cosmic Neutrino ◽

Neutrino Background

We attempt to answer whether neutrinos and antineutrinos, such as those in the cosmic neutrino background, would clusterize among themselves or even with other dark-matter particles, under certain time span, say 1 Gyr. With neutrino masses in place, the similarity with the ordinary matter increases and so is our confidence for neutrino clustering if time is long enough. In particular, the clusterings could happen with some seeds (cf. see the text for definition), the chance in the dark-matter world to form dark-matter galaxies increases. If the dark-matter galaxies would exist in a time span of 1 Gyr, then they might even dictate the formation of the ordinary galaxies (i.e. the dark-matter galaxies get formed first); thus, the implications for the structure of our Universe would be tremendous.

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