We consider the possibility of the detection of $^3$HeII hyperfine line (rest
frequency, $8.67 \, GHz$) emission from ionized zones around accreting
black holes (BHs) formed at high redshifts, $z=15--30$. We show that the
brightness temperature in 8.67GHz line increases and reaches a peak value after
the accretion onto the BH exhausts and HeIII recombines into HeII. This period
of brightening last up to 40~million years. We find that during this period the
maximum brightness temperature reaches $0.2--0.5 \mu$K, depending
on the epoch when such a black hole starts growing. The maximum angular size of
the region emitting in the hyperfine line is around $0.5'$. The flux from such
a region ($0.3 \, nJy$) is too small to be detected by SKA1-MID. The
RMS of the collective flux from many emitting regions from a volume bounded by
the synthesized beam and the band-width of SKA1-MID might reach 100~nJy, which
is potentially detectable by SKA1-MID.
Description
Probing primordial $^3$He from hyperfine line afterglows around supercritical black holes
%0 Generic
%1 vasiliev2019probing
%A Vasiliev, Evgenii O.
%A Sethi, Shiv K.
%A Shchekinov, Yuri A.
%D 2019
%K tifr
%T Probing primordial $^3$He from hyperfine line afterglows around
supercritical black holes
%U http://arxiv.org/abs/1910.08622
%X We consider the possibility of the detection of $^3$HeII hyperfine line (rest
frequency, $8.67 \, GHz$) emission from ionized zones around accreting
black holes (BHs) formed at high redshifts, $z=15--30$. We show that the
brightness temperature in 8.67GHz line increases and reaches a peak value after
the accretion onto the BH exhausts and HeIII recombines into HeII. This period
of brightening last up to 40~million years. We find that during this period the
maximum brightness temperature reaches $0.2--0.5 \mu$K, depending
on the epoch when such a black hole starts growing. The maximum angular size of
the region emitting in the hyperfine line is around $0.5'$. The flux from such
a region ($0.3 \, nJy$) is too small to be detected by SKA1-MID. The
RMS of the collective flux from many emitting regions from a volume bounded by
the synthesized beam and the band-width of SKA1-MID might reach 100~nJy, which
is potentially detectable by SKA1-MID.
@misc{vasiliev2019probing,
abstract = {We consider the possibility of the detection of $^3$HeII hyperfine line (rest
frequency, $8.67 \, \rm GHz$) emission from ionized zones around accreting
black holes (BHs) formed at high redshifts, $z=15\hbox{--}30$. We show that the
brightness temperature in 8.67GHz line increases and reaches a peak value after
the accretion onto the BH exhausts and HeIII recombines into HeII. This period
of brightening last up to 40~million years. We find that during this period the
maximum brightness temperature reaches $\simeq 0.2\hbox{--}0.5 \mu$K, depending
on the epoch when such a black hole starts growing. The maximum angular size of
the region emitting in the hyperfine line is around $0.5'$. The flux from such
a region ($\simeq 0.3 \, \rm nJy$) is too small to be detected by SKA1-MID. The
RMS of the collective flux from many emitting regions from a volume bounded by
the synthesized beam and the band-width of SKA1-MID might reach 100~nJy, which
is potentially detectable by SKA1-MID.},
added-at = {2019-10-22T07:54:11.000+0200},
author = {Vasiliev, Evgenii O. and Sethi, Shiv K. and Shchekinov, Yuri A.},
biburl = {https://www.bibsonomy.org/bibtex/2193f13fa4bd19eb51bb5c175427042e5/citekhatri},
description = {Probing primordial $^3$He from hyperfine line afterglows around supercritical black holes},
interhash = {d3d4f07b3848befe5a7f0dc9c75d85f8},
intrahash = {193f13fa4bd19eb51bb5c175427042e5},
keywords = {tifr},
note = {cite arxiv:1910.08622Comment: 7 pages, 2 figures, accepted in MNRAS},
timestamp = {2019-10-22T07:54:11.000+0200},
title = {Probing primordial $^3$He from hyperfine line afterglows around
supercritical black holes},
url = {http://arxiv.org/abs/1910.08622},
year = 2019
}