New integrable extension of the Hubbard chain with variable range hopping

New integrable variant of the one-dimensional Hubbard model with variable-range correlated hopping is studied. The Hamiltonian is constructed by applying the quantum inverse scattering method on the infinite interval at zero density to the one-parameter deformation of the L-matrix of the Hubbard model. By construction, this model has Y(su(2))$\oplus$Y(su(2)) symmetry in the infinite chain limit. Multiparticle eigenstates of the model are investigated through this method.Comment: 25 pages, LaTeX, no figure

First hours of the GRB 030329 optical afterglow

We present the first results of the observations of the extremely bright optical afterglow of gamma-ray burst (GRB) 030329 with the 1.5m Russian-Turkish telescope RTT150 (TUBITAK National Observatory, Bakyrlytepe, Turkey). RTT150 was one of the first 1.5m-class telescopes pointed to the afterglow. Observations were started approximately 6 hours after the burst. During the first 5 hours of our observations the afterglow faded exactly as a power law with index -1.19+-0.01 in each of the BVRI Bessel filters. After that, in all BVRI filters simultaneously we observe a steepening of the power law light curve. The power law decay index smoothly approaches the value ~= -1.9, observed by other observatories later. This power law break occurs at t-t_0 =0.57 days and lasts for +-0.1 days. We observe no variability above the gradual fading with the upper limits 10--1% on time scales 0.1--1000s. Spectral flux distribution in four BVRI filters corresponds to the power law spectrum with spectral index \alpha=0.66+-0.01. The change of the power law decay index in the end of our observations can be interpreted as a signature of collimated ultrarelativistic jet. The afterglow flux distribution in radio, optical and x-rays is consistent with synchrotron spectrum. We continue our observations of this unique object with RTT150.Comment: Astronomy Letters, Vol. 29, No. 9, p. 573; 6 pages, 5 figures; pagination corrected; the original Russian version can be found at http://hea.iki.rssi.ru/~br/030329/pfh030329.pd

Additional spectroscopic redshift measurements for galaxy clusters from the First Planck Catalogue

We present the results of spectroscopic redshift measurements for the galaxy clusters from the first all-sky Planck catalogue of the Sunyaev-Zeldovich sources, that have been mostly identified by means of the optical observations performed previously by our team (Planck Collaboration, 2015a). The data on 13 galaxy clusters at redshifts from z=~0.2 to z=~0.8, including the improved identification and redshift measurement for the cluster PSZ1 G141.73+14.22 at z=0.828, are provided. The measurements were done using the data from Russian-Turkish 1.5-m telescope (RTT-150), 2.2-m Calar Alto Observatory telescope, and 6-m SAO RAS telescope (Bolshoy Teleskop Azimutalnyi, BTA).Comment: published in Astronomy Letter

Optical observations of SBS1520+530 at TUG

We present the light curves of the components of gravitationally lensed source SBS1520+530 in Rc band, obtained during the interval 2001-2005 with the 1.5 m Russian-Turkish Telescope RTT150 at TÜBITAK National Observatory of Turkey. The time delay of brightness fluctuations between the two components of the gravitationally double-imaged quasar corresponding to 2001-2002 period of observations is determined. Using all the available data, at least two microlensing events, one of them with long-time linear behavior and second one with duration of a few hundred days, are detected. © 2008 Springer-Verlag Berlin Heidelberg

A multiwavelength study of Swift GRB 060111B constraining the origin of its prompt optical emission

In this work, we present the results obtained from a multi-wavelength campaign, as well as from the public Swift/BAT, XRT, and UVOT data of GRB 060111B for which a bright optical emission was measured with good temporal resolution during the prompt phase. We identified the host galaxy at R~25 mag; its featureless spectral continuum and brightness, as well as the non-detection of any associated supernova 16 days after the trigger and other independent redshift estimates, converge to z~1-2. From the analysis of the early afterglow SED, we find that non-negligible host galaxy dust extinction, in addition to the Galactic one, affects the observed flux in the optical regime. The extinction-corrected optical-to-gamma-ray spectral energy distribution during the prompt emission shows a flux density ratio $F_{\gamma}/F_{opt}$=0.01-0.0001 with spectral index $\beta_{\gamma,opt}> \beta_{\gamma}$, strongly suggesting a separate origin of the optical and gamma-ray components. This result is supported by the lack of correlated behavior in the prompt emission light curves observed in the two energy domains. The properties of the prompt optical emission observed during GRB 060111B favor interpretation of this optical light as radiation from the reverse shock in a thick shell limit and in the slow cooling regime. The expected peak flux is consistent with the observed one corrected for the host extinction, likely indicating that the starting time of the TAROT observations is very near to or coincident with the peak time. The estimated fireball initial Lorentz factor is >260-360 at z=1-2, similar to the Lorentz factors obtained from other GRBs. GRB 060111B is a rare, good test case of the reverse shock emission mechanism in both the X-ray and optical energy ranges.Comment: Accepted for publication in Astronomy and Astrophysics, 15 pages,10 figures and 7 table

An experience of scaling and intensifying the industrial production of the Gam-COVID-Vac vector adenovirus vaccine in the limiting conditions of the pandemic

The COVID-19 pandemic has presented a global challenge to the health system. More than 200 years of world epidemiological experience since the first mass use of vaccines have convincingly shown that effective vaccines are the key tools in the fight against dangerous infectious diseases, especially epidemic and pandemic ones. In the context of a rapidly spreading pandemic of a new infectious agent, it is crucial not only to develop fundamentally new vaccines, but also to be able to quickly organise their large-scale production. In the Russian Federation, in 2020, a team of the National Research Centre for Epidemiology and Microbiology named after Honorary Academician N.F. Gamaleya developed an innovative vector vaccine, Gam-COVID-Vaс, for the prevention of coronavirus disease caused by the SARS-CoV-2 virus. A number of pharmaceutical companies faced the challenge of producing the vaccine. The aim of the study was to optimise the production technology of Gam-COVID-Vac for scaling and increasing the production capacity. In the course of the work, the authors established critical quality attributes of the product, optimised analytical methods for their control, identified poorly scalable technological stages, streamlined the technological process before its transfer to production, and modified non-scalable and technologically unfeasible stages. The work resulted in the launch of industrial-scale production of active pharmaceutical ingredients for both components of Gam-COVID-Vac, which made it possible not only to meet the critical need for COVID-19 immunoprophylaxis in the Russian Federation, but also to supply this vaccine to a number of foreign countries

Fast optical variability of SS 433

We study the optical variability of the peculiar Galactic source SS 433 using the observations made with the Russian Turkish 1.5-m telescope (RTT150). A simple technique which allows to obtain high-quality photometric measurements with 0.3-1 s time resolution using ordinary CCD is described in detail. Using the test observations of nonvariable stars, we show that the atmospheric turbulence introduces no significant distortions into the measured light curves. Therefore, the data obtained in this way are well suited for studying the aperiodic variability of various objects. The large amount of SS 433 optical light curve measurements obtained in this way allowed us to obtain the power spectra of its flux variability with a record sensitivity up to frequencies of ~0.5 Hz and to detect its break at frequency =~2.4e-3 Hz. We suggest that this break in the power spectrum results from the smoothing of the optical flux variability due to a finite size of the emitting region. Based on our measurement of the break frequency in the power spectrum, we estimated the size of the accretion-disk photosphere as 2e12 cm. We show that the amplitude of the variability in SS 433 decreases sharply during accretion-disk eclipses, but it does not disappear completely. This suggests that the size of the variable optical emission source is comparable to that of the normal star whose size is therefore R_O \approx 2e12 cm \approx 30 R_sun. The decrease in flux variability amplitude during eclipses suggests the presence of a nonvariable optical emission component with a magnitude m_R=~13.2.Comment: 12 pages, 11 figures. Accepted for publication in Astronomy Letters. The original version in Russian is available at http://hea.iki.rssi.ru/rtt150/ru/ss433_pazh10/pss433_fast.pd

Comparative safety evaluation of intranasal and intramuscular immunisation with Ad26 and Ad5-vectored vaccines to prevent coronavirus infection

Scientific relevance. Intranasal vaccination may dramatically change current approaches to mass immunisation against various infections, shifting the focus from inducing systemic humoral and cellular immune responses to developing mucosal immunity and protective barriers on the mucous membranes, which are entry points for pathogens. Therefore, the safety of switching from intramuscular to intranasal vaccination should be evaluated.Aim. This study aimed to compare the safety of intranasal and intramuscular vaccination using the intermediate results of the phase III VCI-COV-III clinical trial in healthy volunteers.Materials and methods. The evaluation of the safety profile was based on the adverse events and adverse drug reactions (ADRs) documented by investigators in the interim report on the randomised, double-blind clinical trial of the Salnavac intranasal vaccine (InV) and the Gam-COVID-Vac intramuscular vaccine (ImV) against coronavirus infection. The report covered 42 days of observation in 137 healthy volunteers.Results. ADRs were reported for 17/68 (25%) and 30/69 (43.5%) volunteers in the InV group and the ImV group, respectively (p=0.036). The ADRs reported for the InV group were systemic and local, short-term, mostly mild, and generally consistent in incidence and nature with the ADRs typically observed with other nasal products.Conclusions. According to the preliminary data obtained in the clinical trial, the InV demonstrates a high level of safety. Its safety profile is comparable with those of other intranasal and intramuscular vaccines for the prevention of coronavirus infection

Analysis of optical light curves for the components of the gravitationally lensed quasar SBS 1520+530 based on observations with the 1.5-m RTT-150 telescope in 2001-2005

We present the R c-band light curves for components A and B of the gravitationally lensed quasar SBS 1520+530 obtained during 2001-2005 with the 1.5-m Russian-Turkish Telescope (RTT-150) at the TUBITAK National Observatory (Turkey). Based on an analysis of the data for the period 2001-2002, we have estimated the time delay of the brightness fluctuations between components A and B of the quasar to be 128 days. This time delay agrees with its previously published values for the periods 1999-2001 and 2003-2004. Using all of the published data on the brightnesses of components A and B of SBS 1520+530 for the 6-year period, we have found at least two microlensing events. One event has the pattern of a long-term linear trend; the duration of the other event is several hundred days. © Pleiades Publishing, Inc., 2006