Recent results of the searches for Supersymmetry in final states with one or two leptons at CMS are presented. Many Supersymmetry scenarios, including the Constrained Minimal Supersymmetric extension of the Standard Model (CMSSM), predict a substantial amount of events containing leptons, while the largest fraction of Standard Model background events -which are QCD interactions -gets strongly reduced by requiring isolated leptons. The analyzed data was taken in 2011 and corresponds to an integrated luminosity of approximately L = 1 fb −1 . The center-of-mass energy of the pp collisions was √ s = 7 TeV.
Ultracold polar molecules offer the possibility of exploring quantum gases with interparticle interactions that are strong, long-range, and spatially anisotropic. This is in stark contrast to the dilute gases of ultracold atoms, which have isotropic and extremely short-range, or "contact", interactions. The large electric dipole moment of polar molecules can be tuned with an external electric field; this provides unique opportunities such as control of ultracold chemical reactions, quantum information processing, and the realization of novel quantum many-body systems. In spite of intense experimental efforts aimed at observing the influence of dipoles on ultracold molecules, only recently have sufficiently high densities been achieved. Here, we report the observation of dipolar collisions in an ultracold molecular gas prepared close to quantum degeneracy. For modest values of an applied electric field, we observe a dramatic increase in the loss rate of fermionic KRb molecules due to ultrcold chemical reactions. We find that the loss rate has a steep power-law dependence on the induced electric dipole moment, and we show that this dependence can be understood with a relatively simple model based on quantum threshold laws for scattering of fermionic polar molecules. We directly observe the spatial anisotropy of the dipolar interaction as manifested in measurements of the thermodynamics of the dipolar gas. These results demonstrate how the long-range dipolar interaction can be used for electric-field control of chemical reaction rates in an ultracold polar molecule gas. The large loss rates in an applied electric field suggest that creating a long-lived ensemble of ultracold polar molecules may require confinement in a two-dimensional trap geometry to suppress the influence of the attractive dipolar interactions
Ultracold molecules offer entirely new possibilities for the control of quantum processes due to their rich internal structure. Recently, near quantum degenerate gases of molecules have been prepared in their rovibronic ground state. For future experiments, it is crucial to also control their hyperfine state. Here, we report the preparation of a rovibronic ground state molecular quantum gas in a single hyperfine state and in particular in the absolute lowest quantum state. The demonstrated and presented scheme is general for bialkali polar molecules and allows the preparation of molecules in a single hyperfine state or in an arbitrary coherent superposition of hyperfine states. The scheme relies on electric-dipole, two-photon microwave transitions through rotationally excited states and makes use of electric nuclear quadrupole interactions to transfer molecular population between different hyperfine states.PACS numbers: 03.75. Kk, 03.75.Ss, 32.80.Pj, 34.20.Cf, The field of ultracold atomic quantum gases draws much of its success from the unprecedented ability to precisely control the external and internal degrees of freedom of the gas. Control over the external, or motional degree of freedom, comes from realizing ultracold gases in almost arbitrary confining potentials provided by magnetic or optical fields. The internal degrees of freedom, namely the quantum states of the atoms, can be manipulated by driving rf [1] or optical transitions. Because collisional interactions in the gas depend on the internal states, precise control of these quantum states is a prerequisite for creating trapped samples that are stable against inelastic collisions as well as for accessing scattering resonances in order to tune the interparticle interactions [2]. Manipulation of the internal degrees of freedom is also essential in the study of quantum gases, where samples of identical bosons or fermions in a single internal state can behave very differently from spin mixtures. Finally, the precise control of the atomic states is key to quantum information schemes where one seeks to initialize and manipulate atoms as quantum qubits with long coherence times [3].The precise control of external and internal degrees of freedom will be equally important for the emerging field of ultracold molecular quantum gases. This field has recently seen tremendous progress through the first preparation of near quantum degenerate gas of bialkali molecules in the rovibrational ground state of the electronic ground molecular potential [4,5]. These experiments have demonstrated a high degree of control over the electronic, vibrational and rotational degrees of freedom of ultracold molecules via two-photon optical Raman transitions [6,7]. However, most molecules will additionally have hyperfine structure within a single rotational and vibrational level [8], and, as is true for ultracold atomic gases, control of these quantum degrees of freedom is essential for future experiments. In particular, for experimental efforts to achieve a Bose-Einstein condensate...
We report the creation and characterization of a near quantum-degenerate gas of polar 40K-87Rb molecules in their absolute rovibrational ground state. Starting from weakly bound heteronuclear KRb Feshbach molecules, we implement precise control of the molecular electronic, vibrational, and rotational degrees of freedom with phase-coherent laser fields. In particular, we coherently transfer these weakly bound molecules across a 125 THz frequency gap in a single step into the absolute rovibrational ground state of the electronic ground potential. Phase coherence between lasers involved in the transfer process is ensured by referencing the lasers to two single components of a phase-stabilized optical frequency comb. Using these methods, we prepare a dense gas of 4 x 10(4) polar molecules at a temperature below 400 nK. This fermionic molecular ensemble is close to quantum degeneracy and can be characterized by a degeneracy parameter of T/T(F) = 3. We have measured the molecular polarizability in an optical dipole trap where the trap lifetime gives clues to interesting decay mechanisms. Given the large measured dipole moment of the KRb molecules of 0.5 Debye, the study of quantum degenerate molecular gases interacting via strong dipolar interactions is now within experimental reach. PACS numbers: 37.10.Mn, 37.10.Pq.
Korea (the Republic of) Vitamin D receptor (VDR) as a ligand-dependent transcription factor forms a heterodimer with retinoid X receptor (RXR) to activate vitamin D response elements-associated various cellular genes during hair growth. Lithocholic acid (LCA) is known to be a naturally produced VDR ligand to induce VDR-RXR conformation. Previous studies demonstrated that the absence of VDR and RXRa ultimately resulted in alopecia development in mouse. However, since the role of LCA is not clear in hair cycling, we examined the functional mechanism of LCA in human dermal papilla cells (hDPCs). Treatment of hDPC cells with LCA significantly increased cellular proliferation together with the enhanced expression of VDR, RXRa,
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