Rubin-LSST

Abstract:

We present Hubble Space Telescope Wide Field Planetary Camera 2 I-band imaging for a sample of nine hyperluminous infrared galaxies (HLIRGs) spanning a redshift range 0.45 < z < 1.34. Three of the sample have morphologies showing evidence for interactions and six are quasi-stellar objects (QSOs). Host galaxies in the QSOs are detected reliably out to z ∼ 0.8. The detected QSO host galaxies have an elliptical morphology with scalelengths spanning 6.5 < re (kpc) < 88 and absolute k-corrected magnitudes spanning −24.5 < MI < −25.2. There is no clear correlation between the infrared (IR) power source and the optical morphology. None of the sources in the sample, including F15307+3252, shows any evidence for gravitational lensing. We infer that the IR luminosities are thus real. Based on these results, and previous studies of HLIRGs, we conclude that this class of object is broadly consistent with being a simple extrapolation of the ULIRG population to higher luminosities; ULIRGs being mainly violently interacting systems powered by starbursts and/or active galactic nuclei. Only a small number of sources, the infrared luminosities of which exceed 1013 L⊙, are intrinsically less luminous objects that have been boosted by gravitational lensing.

Abstract:

This report provides a comprehensive overview of the prospects for B physics at the Tevatron. The work was carried out during a series of workshops starting in September 1999. There were four working groups: 1) CP Violation, 2) Rare and Semileptonic Decays, 3) Mixing and Lifetimes, 4) Production, Fragmentation and Spectroscopy. The report also includes introductory chapters on theoretical and experimental tools emphasizing aspects of B physics specific to hadron colliders, as well as overviews of the CDF, D0, and BTeV detectors, and a Summary.

Abstract:

Using a 13.7 fb^-1 sample of continuum two-jet e ⁺e^- → qq̄ events collected with the CLEO detector, we have searched for correlations between Λ and Λ̄ particles, specifically in cases where the opening angle between the two particles is large and each has momentum > 1 GeV/c. Such correlations may indicate the presence of baryon number conservation at the primary quark level. A previous CLEO study of ΛcΛc correlations indicated direct, associated production of primary charmed baryons Λc: e⁺e^- → cc̄ → ΛcΛ̄c. That effect was not observed in Monte Carlo simulations. Our current search for similar direct, associated production of Λ baryons at the primary quark level (e⁺e ^- → ss̄ → ΛΛ̄, e.g.) qualitatively indicates a similar effect, although it relies on a Monte Carlo dependent subtraction of background ΛΛ̄ production (based on the default JETSET 7.4 event generator). © 2002 The American Physical Society.