The potential of the ground state of NaRb

The X$^{1}\Sigma ^{+}$ state of NaRb was studied by Fourier transform spectroscopy. An accurate potential energy curve was derived from more than 8800 transitions in isotopomers $^{23}$Na$^{85}$Rb and $^{23}$Na$^{87}$Rb. This potential reproduces the experimental observations within their uncertainties of 0.003 \rcm to 0.007 \rcm. The outer classical turning point of the last observed energy level ($v''=76$, $J''=27$) lies at $\approx 12.4$ \AA, leading to a energy of 4.5 \rcm below the ground state asymptote.Comment: 8 pages, 6 figures and 2 table

Formation of ultracold RbCs molecules by photoassociation

The formation of ultracold metastable RbCs molecules is observed in a double species magneto-optical trap through photoassociation below the ^85Rb(5S_1/2)+^133Cs(6P_3/2) dissociation limit followed by spontaneous emission. The molecules are detected by resonance enhanced two-photon ionization. Using accurate quantum chemistry calculations of the potential energy curves and transition dipole moment, we interpret the observed photoassociation process as occurring at short internuclear distance, in contrast with most previous cold atom photoassociation studies. The vibrational levels excited by photoassociation belong to the 5th 0^+ or the 4th 0^- electronic states correlated to the Rb(5P_1/2,3/2)+Cs(6S_1/2) dissociation limit. The computed vibrational distribution of the produced molecules shows that they are stabilized in deeply bound vibrational states of the lowest triplet state. We also predict that a noticeable fraction of molecules is produced in the lowest level of the electronic ground state

Calculation of the interspecies s-wave scattering length in an ultracold Na-Rb vapor

We report the calculation of the interspecies scattering length for the sodium-rubidium (Na-Rb) system. We present improved hybrid potentials for the singlet $X^1\Sigma^+$ and triplet $a^3\Sigma^+$ ground states of the NaRb molecule, and calculate the singlet and triplet scattering lengths $a_{s}$ and $a_{t}$ for the isotopomers $^{23}$Na$^{87}$Rb and $^{23}$Na$^{85}$Rb. Using these values, we assess the prospects for producing a stable two-species Bose-Einstein condensate in the Na-Rb system.Comment: v2: report correct units in Table captions, fix error in conclusions for $^{23}$Na$^{85}$Rb TBEC. Otherwise, more concise presentation, typos fixed. 6 pages, 1 figur

Dark resonances for ground state transfer of molecular quantum gases

One possible way to produce ultracold, high-phase-space-density quantum gases of molecules in the rovibronic ground state is given by molecule association from quantum-degenerate atomic gases on a Feshbach resonance and subsequent coherent optical multi-photon transfer into the rovibronic ground state. In ultracold samples of Cs_2 molecules, we observe two-photon dark resonances that connect the intermediate rovibrational level |v=73,J=2> with the rovibrational ground state |v=0,J=0> of the singlet $X^1\Sigma_g^+$ ground state potential. For precise dark resonance spectroscopy we exploit the fact that it is possible to efficiently populate the level |v=73,J=2> by two-photon transfer from the dissociation threshold with the stimulated Raman adiabatic passage (STIRAP) technique. We find that at least one of the two-photon resonances is sufficiently strong to allow future implementation of coherent STIRAP transfer of a molecular quantum gas to the rovibrational ground state |v=0,J=0>.Comment: 7 pages, 4 figure

Implementation of the Principles of the Convention on the Rights of the Child in the Activities of Commissions on Minors' Affairs and Protection of Their Rights

The article examines the role of the Commission for Juvenile Affairs and the protection of their rights as a coordinating body of the subjects of the system of prevention of neglect and delinquency of minors.В статье рассматривается реализация государственной политики в области охраны прав детей

The coupling of the X1Σ+^{1}\Sigma ^{+} and a3Σ+^{3}\Sigma ^{+} states of KRb

A comprehensive study of the electronic states at the 4s+5s asymptote in KRb is presented. Abundant spectroscopic data on the \astate state were collected by Fourier-transform spectroscopy which allow to determine an accurate experimental potential energy curve up to 14.8 \AA . The existing data set (C. Amiot et al. J. Chem. Phys. 112, 7068 (2000)) on the ground state \Xstate was extended by several additional levels lying close to the atomic asymptote. In a coupled channels fitting routine complete molecular potentials for both electronic states were fitted. Along with the line frequencies of the molecular transitions, recently published positions of Feshbach resonances in $^{40}$K and $^{87}$Rb mixtures (F. Ferlaino et al. Phys. Rev. A 74, 039903 (2006)) were included in the fit. This makes the derived potential curves capable for an accurate description of observed cold collision features so far. Predictions of scattering lengths and Feshbach resonances in other isotopic combinations are reported.Comment: 14 pages, 5 figure

Hydrogen-like nitrogen radio line from hot interstellar and warm-hot intergalactic gas

Hyperfine structure lines of highly-charged ions may open a new window in observations of hot rarefied astrophysical plasmas. In this paper we discuss spectral lines of isotopes and ions abundant at temperatures 10^5-10^7 K, characteristic for warm-hot intergalactic medium, hot interstellar medium, starburst galaxies, their superwinds and young supernova remnants. Observations of these lines will allow to study bulk and turbulent motions of the observed target and will broaden the information about the gas ionization state, chemical and isotopic composition. The most prospective is the line of the major nitrogen isotope having wavelength 5.65 mm (Sunyaev and Churazov 1084). Wavelength of this line is well-suited for observation of objects at z=0.15-0.6 when it is redshifted to 6.5-9 mm spectral band widely-used in ground-based radio observations, and, for example, for z>=1.3, when the line can be observed in 1.3 cm band and at lower frequencies. Modern and future radio telescopes and interferometers are able to observe the absorption by 14-N VII in the warm-hot intergalactic medium at redshifts above z=0.15 in spectra of brightest mm-band sources. Sub-millimeter emission lines of several most abundant isotopes having hyperfine splitting might also be detected in spectra of young supernova remnants.Comment: 12 pages, 5 figures, accepted by Astronomy Letters; v3: details added; error fixe

Formation and interactions of cold and ultracold molecules: new challenges for interdisciplinary physics

Progress on researches in the field of molecules at cold and ultracold temperatures is reported in this review. It covers extensively the experimental methods to produce, detect and characterize cold and ultracold molecules including association of ultracold atoms, deceleration by external fields and kinematic cooling. Confinement of molecules in different kinds of traps is also discussed. The basic theoretical issues related to the knowledge of the molecular structure, the atom-molecule and molecule-molecule mutual interactions, and to their possible manipulation and control with external fields, are reviewed. A short discussion on the broad area of applications completes the review.Comment: to appear in Reports on Progress in Physic

The impact of antibodies to human glycoprotein CD4 and gamma-interferon on the t-cell immunity and the cytokine levels in patients co-infected with HIV/HCV during the antiretroviral therapy

Objective: This work was to estimate the influence of antibodies to human glycoprotein CD4 and IFN-γ on the T-cell immunity and the cytokine levels in patients with HIV and HIV/HCV during the standard antiretroviral therapy. Materials and methods: Randomized clinical trial in parallel groups. 4 groups were included: patients with HIV receiving ART (20) or ART and antibodies (AB) (19) for 3 months; patients with HIV/HCV, receiving ART (17) or ART and AB (20) for 3 months. The obtained data included: CD3+, CD4+, CD8+ cell count; IFN-γ, IL-2 and IL-4 concentrations; HIV viral load. Results: The significant increase of CD4+ cell number and IFN-γ were found in patients receiving ART and antibodies. These changes were followed with more significant decline in the viral load. Conclusion: The antibodies to human glycoprotein CD4 and IFN-γ added to standard ART increased the CD4+ cell count and IFN-γ levels in patients with HIV/HCV, followed by the trend to increase the number of patients with viral load >50 ml-1. Thus, the administration of ART supplemented with antibodies to human glycoprotein CD4 and IFN-γ resulted in the increase of antiviral immunity. Further clinical trials in HIV or HIV patients with co-infections could be recommended