Russian astronomers have observed a tarnishing of the blazar emission of the neutrino

System of then robotic telescope MASTER recorded
change the brightness of the blazar TXS 0506+056 in the optical range, about
coinciding with the time of the registration of neutrinos of high energy from this
direction. In the first frame obtained after about a minute after coming
neutrino source was much dimmer than most obtained in
other time images. However, for the next two hours, he returned to
the average brightness. The obtained data allow to unambiguously associate
neutrinos high energy optical variability of a particular source.
The results were reported on the all-Moscow seminar of astrophysicists named zel’dovich, and accepted for publication
in The Astrophysical Journal Letters.

Neutrino is the lightest with a mass of elementary
particles in the Standard model of particle physics. They can be born in many high-energy
processes that occur in the cores of stars, during supernova explosions, accretion
disks and active galactic nuclei. However, the interaction cross section of neutrinos with other
particles are very small, making them difficult to detect. Until recently, two
the only identified cosmic sources of neutrinos remained
The sun and supernova 1987A.

The complexity of registration of neutrinos complicate experimental elucidation
their role in astrophysics. In particular, even the most advanced neutrino telescope IceCube measures
the particle parameters with noticeable errors. As a result, instead of precise coordinates in the sky,
how come neutrinos, usually we only know that this bearing falls
in the field area of about square degrees. That area gets a huge
variety of sources, and the fields of view of modern large optical
telescopes are generally, much less, that allows them to quickly
to observe the whole area.

It is for these tasks are automatic system
telescopes which have quite large fields of view and is able
independently lock on to the desired features based on incoming alerts. These
tools inferior to the big brothers in terms of image quality and
to be able to fix the most dull objects, but their advantages in
speed and coverage. In particular, these telescopes are allowed
to detect in the optical signal from the merger of neutron stars, which were originally
discovered gravitational-wave antennas.

At the moment, the world exists as a separate automatic
telescopes and groups that combine several devices in different
places of the Earth. One of them is the system MASTER (Mobile Astronomical
The system of Telescopes-Robots), created on the initiative of Professor of Moscow state University Vladimir
Lipunova. At the moment the network MASTER nine telescopes around the world
the ball, including six in our country and one each in Argentina, South Africa and
Spain. The MASTER has received important scientific results, in particular, for the first time registered
the polarization of the intrinsic optical radiation of gamma-ray bursts.

Friday, June 5 at the all-Moscow seminar of astrophysicists
name Zeldovich, Vladimir Lipunov announced a new result of the system MASTER
the observation of optical emission accompanying the registration of neutrinos, IceCube-170922A
in 2017. Telescope MASTER Tavrida in the Crimea received the first shots are necessary
grounds after 73 seconds after the detection of neutrinos (after 27 seconds.
after the appearance of the corresponding alert). It turned out that these
the images of the blazar TXS 0506+056 dimmer than usual on 0,790 ± 0,016 star
values that correspond to the fall of the absolute luminosity is about two times. Through
two hours and the source has returned to its normal level of Shine.

To verify, astronomers have calibrated the brightness of the blazar eight
falling on the same footage the stars whose parameters are known with high
accuracy thanks to the observations of the space telescope Gaia. The standard brightness is determined on
measurement-based on several weeks of the arrival of the neutrinos, and all
various telescopes can system MASTER watched TXS 0506+056, starting in 2005.

It turned out that for the most part observations
the luminosity of a blazar is approximately constant. Markedly it has changed only three times: in
In 2006, when the IceCube is still not working, in 2015, within six months coincides with the
neutrino event IC86b, and in 2017, in the latter case, as the statistical
the significance of the change, and a temporary coincidence with the arrival of the neutrinos is much better.

Scientists also propose a hypothesis that can explain
the decrease in the optical brightness that accompanies the arrival of the neutrinos. The authors write that according to
one of the main theoretical concepts like photons and neutrinos
arise from ultra-relativistic protons in the jet Central super-massive
the black hole in the core of the blazar. However, for the appearance of neutrinos needs to happen
reaction in which a proton is transformed into two PI-meson, while
as in the generation of optical photons via synchrotron radiation of the protons
don’t disappear. In this case, we can assume that for some reason (for example,
because of the instability in the plasma jet), a significant fraction of the protons turned into
peonies, which caused an increased flux of neutrinos provided a check on IceCube, but at the same time
reduced the brightness in the optical range.

Although the blazar TXS 0506+056 immediately after the registration of neutrinos, called the most likely source of events IceCube-170922A, some doubts about the correctness of identifications could be. In particular, he has been actively emit gamma photons of a few months before the registration of neutrinos, high energy cosmic rays from it started to catch only a week later, and no significant variability in the optics, x-ray or gamma-range has not previously been identified, which is associated primarily with the lack of suitable data. The results of the Wizard, submit a new independent and important evidence that TXS 0506+056 was the source.

We wrote extensively about the first registration of neutrinos of ultrahigh energy to the material “Ice”neutrino. Previously, scientists have found in ten years of IceCube data indicate that a possible new extragalactic sources of neutrinos, and anothern team managed to tie neutrinos of ultrahigh energies with flashes of quasars using the long term statistics of the observations of these objects at radio frequencies.

Timur Keshelava

Leave a Reply

Your email address will not be published.