851 research outputs found

    Luminosities of High-Redshift Objects in an Accelerating Universe

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    The results from the Supernova Cosmology Project indicate a relation between cosmic distance and redshift that corresponds to an accelerating Universe, and, as a consequence, the presence of an energy component with negative pressure. This necessitates a re-evaluation of such astrophysical luminosities that have been derived through conventional redshift analyses of, e.g., gamma-ray bursts and quasars. We have calculated corrected luminosity distances within two scenarios; the standard one with a non-zero cosmological constant, and the more recently proposed ``quintessence'', with a slowly evolving energy-density component. We find luminosity corrections from +30 to -40 per cent for redshifts with z=010z=0 - 10. This finding implicates that the SCP data do not, by themselves, require a revision of the current, rather qualitative modeling of gamma-ray bursts and quasar properties.Comment: RevTeX, 4 pages, 2 postscript figures, submitted to PR

    Water cooled contactor for anode in carbon arc mechanism

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    Water cooled contactors for holding rotating carbon arc anod

    A Census of the Avifauna of the FAP 301 Project Area Addenda 1 and 2

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    Report issued on: issued July 25, 1996INHS Technical Report prepared for Illinois Department of Transportatio

    Is Dark Matter made up of Massive Quark Objects?

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    We suggest that dark matter is made up of massive quark objects that have survived from the Big Bang, representing the ground state of ``baryonic'' matter. Hence, there was no overall phase transition of the original quark matter, but only a split-up into smaller objects. We speculate that normal hadronic matter comes about through enforced phase transitions when such objects merge or collide, which also gives rise to the cosmic gamma-ray bursts.Comment: 8 pages Latex, no figures; to be published in the Proceedings of Dark '98, Heidelberg, July 199

    Monolithic narrow-linewidth InGaAsP semiconductor laser for coherent optical communications

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    A design for a monolithic narrow-linewidth InGaAsP diode laser has been developed using a multiple-quantum-well (MQW) extended-passive-cavity distributed-Bragg-reflector (DBR) laser design. Theoretical results indicate that this structure has the potential for a linewidth of 100 kHz or less. To realize this device, a number of the fabrication techniques required to integrate low-loss passive waveguides with active regions have been developed using a DBR laser structure. In addition, the MOCVD growth of InGaAs MQW laser structures has been developed, and threshold current densities as low as 1.6 kA/sq cm have been obtained from broad-stripe InGaAs/InGaAsP separate-confinement-heterostructure MQW lasers

    Vapor phase growth technique and system for several 3-5 compound semiconductors Quarterly technical report

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    Vapor phase growth technique and system for group 3A and 5A compound semiconductor

    Defending legitimate epidemiologic research: combating Lysenko pseudoscience

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    This analysis presents a detailed defense of my epidemiologic research in the May 17, 2003 British Medical Journal that found no significant relationship between environmental tobacco smoke (ETS) and tobacco-related mortality. In order to defend the honesty and scientific integrity of my research, I have identified and addressed in a detailed manner several unethical and erroneous attacks on this research. Specifically, I have demonstrated that this research is not "fatally flawed," that I have not made "inappropriate use" of the underlying database, and that my findings agree with other United States results on this relationship. My research suggests, contrary to popular claims, that there is not a causal relationship between ETS and mortality in the U.S. responsible for 50,000 excess annual deaths, but rather there is a weak and inconsistent relationship. The popular claims tend to damage the credibility of epidemiology. In addition, I address the omission of my research from the 2006 Surgeon General's Report on Involuntary Smoking and the inclusion of it in a massive U.S. Department of Justice racketeering lawsuit. I refute erroneous statements made by powerful U.S. epidemiologists and activists about me and my research and I defend the funding used to conduct this research. Finally, I compare many aspect of ETS epidemiology in the U.S. with pseudoscience in the Soviet Union during the period of Trofim Denisovich Lysenko. Overall, this paper is intended to defend legitimate research against illegitimate criticism by those who have attempted to suppress and discredit it because it does not support their ideological and political agendas. Hopefully, this defense will help other scientists defend their legitimate research and combat "Lysenko pseudoscience.

    Sea Stewards: A Volunteer Ecological Monitoring Program

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    Vapor-phase growth technique and system for several III-V compound semiconductors Interim scientific report

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    Vapor phase growth technique for III-V compound semiconductors containing aluminu
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