%...Journal: PASP
%...MainTag: '<UCP-HEADER'
%R=BibCode
%A=Authors
%B=Abstract
%c=Copyright
%D=Date of publication
%E=Electronic file
%F=Original File
%I=Institute and/or Footnotes
%J-last page
%K=Keywords
%T=Title

%R 2000PASP..112..583I
%F ori/PASPv112n771
%J-585
%T Black Hole 2000: The Astrophysical Era(1). (Millennium Essay).
%A Israel, Werner
%I Canadian Institute for Advanced Research Cosmology Program, Department of
   Physics and Astronomy, University of Victoria, Victoria, BC V8W 3P6, Canada;
   (israel@uvphys.phys.uvic.ca)
%I (1) This Essay is one of a series of invited contributions which will
   appear in the {\em PASP} throughout the year 2000 to mark the upcoming millennium. (Eds.)

%R 2000PASP..112..586S
%F ori/PASPv112n771
%J-593
%T The Lyman Continuum Polarization Rise in the QSO PG 1222+228.
%A Shields, Gregory A.
%I Department of Astronomy, University of Texas, Austin, TX 78712; (shields@astro.as.utexas.edu)
%B Some QSOs show an abrupt, strong rise in polarization at rest wavelength ~750
   {AA}. If this arises in the atmosphere of an accretion disk around a supermassive
   black hole, it may have diagnostic value. In PG 1222+228, the polarization
   rise occurs at the wavelength of a sharp drop in flux. We examine and reject
   interpretations of this feature involving a high-velocity outflow. The observations
   agree with a model involving several intervening Lyman limit systems, two
   of which happen to coincide with the Lyman continuum polarization rise. After correction
   for the Lyman limit absorption, the continuum shortward of 912 {AA} is consistent
   with a typical power-law slope, {alpha}{approx}-1.8. This violates the apparent pattern
   for the Lyman limit polarization rises to occur only in ``candidate Lyman
   edge QSOs.'' The corrected, polarized flux rises strongly at the wavelength
   of the polarization rise, resembling the case of PG 1630+377. The rise in
   polarized flux places especially stringent requirements on models.
%K Galaxies: Active
%K Polarization
%K Galaxies: Quasars: General

%R 2000PASP..112..594W
%F ori/PASPv112n771
%J-598
%T C32: A Young Star Cluster in IC 1613.
%A Wyder, Ted K.
%A Hodge, Paul W.
%I Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195-1580;
   (wyder@astro.washington.edu), (hodge@astro.washington.edu) and
%A Cole, Andrew
%I Department of Physics and Astronomy, 640 Lederle Grad Research Center, University
   of Massachusetts, Amherst, MA 01003; (cole@condor.astro.umass.edu)
%B The Local Group irregular galaxy IC 1613 has remained an enigma for
   many years because of its apparent lack of star clusters. We report the successful
   search for clusters among several of the candidate objects identified many
   years ago on photographic plates. We have used a single {\em Hubble Space
   Telescope} WFPC2 pointing and a series of images obtained with the WIYN telescope
   under exceptional seeing conditions, examining a total of 23 of the previously
   published candidates. All but six of these objects were found to be either
   asterisms or background galaxies. Five of the six remaining candidates possibly
   are small, sparse clusters, and the sixth, C32, is an obvious cluster. It
   is a compact, young object, with an age of less than 10 million years and
   a total absolute magnitude of M_V_=-5.78+/-0.16 within a radius of 13 pc.
%K galaxies: individual (IC 1613)
%K Galaxies: Star Clusters

%R 2000PASP..112..599S
%F ori/PASPv112n771
%J-609
%T X-Ray Observations of Two Intermediate-Age Open Clusters: NGC 1039 and NGC
   3532.
%A Simon, Theodore (1)
%I Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu,
   HI 96822
%B Soft X-ray images of the intermediate-age (~250 Myr) NGC 1039 and NGC
   3532 open star clusters have been acquired with the {\em ROSAT} High Resolution
   Imager, resulting in the detection of 75 sources above a 3 {sigma} detection
   level of L_X_=~2.5x10^29^ ergs.s^-1^. Roughly half the sources detected in
   both images have likely optical counterparts from earlier ground-based surveys.
   The remainder are either prospective cluster members or foreground/background
   stars, which can be decided only through additional photometry, spectroscopy,
   and proper-motion studies. There is some indication (at the 98% confidence
   level) that solar-type stars in both clusters, and in the similarly aged NGC
   6475 cluster, may lack the extreme rotation and activity levels shown by
   those in the much younger Pleiades and {alpha} Persei clusters, but a detailed
   assessment of the coronal X-ray properties of these clusters must await more
   sensitive observations in the future. If confirmed, this finding could help
   to rule out the possibility that stellar dynamo activity and rotational braking
   are controlled by a rapidly spinning central core as stars pass through this
   phase of evolution from the Pleiades stage to that represented by the Hyades.
%K open clusters and associations: individual (NGC 1039, NGC 3532)
%K X-Rays
%I (1) {\em ROSAT} Guest Observer.

%R 2000PASP..112..610G
%F ori/PASPv112n771
%J-613
%T {\em Hubble Space Telescope} Observations of M Subdwarfs.
%A Gizis, John E. (1)
%I Five College Astronomy Department, Department of Physics and Astronomy, University
   of Massachusetts, Amherst, MA 01003and
%A Reid, I.Neill
%I Department of Physics and Astronomy, University of Pennsylvania, 209 South
   33d Street, Philadelphia, PA 19104-6396
%B We present the results of a {\em Hubble Space Telescope} snapshot program
   to search for very low mass stellar companions to nearby M subdwarfs. None
   of our nine targetted metal-poor primaries has companions more massive than
   the hydrogen burning limit, implying that the halo binary fraction is equal
   to or less than the Galactic disk binary fraction below 0.3 {\em M}_{sun}_.
   In addition, the more distant tertiary VB 12, an sdM3.0 companion to an F
   subdwarf double, is also unresolved. We show that the relation between WFPC2
   F555W and F850LP photometry and ground-based V,I photometry is consistent
   with theoretical expectations. We also report that two recently observed
   Hyades M dwarfs appear single.
%K Stars: Binaries: General
%K Stars: Low-Mass, Brown Dwarfs
%K Stars: Population II
%I (1) Current address: Infrared Processing and Analysis Center, 100-22, California
   Institute of Technology, Pasadena, CA 91125; (gizis@ipac.caltech.edu).

%R 2000PASP..112..614W
%F ori/PASPv112n771
%J-624
%T Biases in Expansion Distances of Novae Arising from the Prolate Geometry of
   Nova Shells.
%A Wade, Richard A. (1)(2)
%A Harlow, Jason J.B. (1)(3)
%A Ciardullo, Robin (1)(4)
%B Expansion distances (or expansion parallaxes) for classical novae are
   based on comparing a measurement of the shell expansion velocity, multiplied
   by the time since outburst, with some measure of the angular size of the
   shell. We review and formalize this method in the case of prolate spheroidal
   shells. For such shells there is no unique angular size except when the shell
   is seen pole-on, and several different measures of angular size have been
   used in the literature. We present expressions for the maximum line-of-sight
   velocity from a complete, expanding shell and for its projected major and
   minor axes, in terms of the intrinsic axis ratio and the inclination of the
   polar axis to the line of sight. For six distinct definitions of ``angular size''
   we tabulate the error in distance that is introduced under the assumption
   of spherical symmetry (i.e., without correcting for inclination and axis
   ratio). The errors can be significant and systematic and can affect studies
   of novae whether considered individually or statistically. Each of the six
   estimators overpredicts the distance when the polar axis is close to the
   line of sight, and most underpredict the distance when the polar axis is
   close to the plane of the sky. Use of the straight mean of the projected
   semimajor and semiminor axes gives the least distance bias for an ensemble
   of randomly oriented prolate shells, and we recommend this method when individual
   inclinations and axis ratios cannot be ascertained. The best individual expansion
   distances, however, result from a full spatio-kinematic modeling of the nova
   shell. We discuss several practical complications that affect expansion distance
   measurements of real nova shells. We recommend that nova shell expansion
   distances be based on velocity and angular size measurements made contemporaneously
   if possible and that the same ions and transitions be used for the imaging
   and velocity measurements. We emphasize the need for complete and explicit reporting
   of measurement procedures and results, regardless of the specific method
   used.
%K Stars: Circumstellar Matter
%K Stars: Novae, Cataclysmic Variables
%I (1) Department of Astronomy and Astrophysics, The Pennsylvania State University,
   525 Davey Laboratory, University Park, PA 16802-6305.
%I (2) (wade@astro.psu.edu).
%I (3) Present address: Department of Physics, University of the Pacific,
   3601 Pacific Avenue, Stockton, CA 95211-0197; (jharlow@uop.edu).
%I (4) (rbc@astro.psu.edu).

%R 2000PASP..112..625P
%F ori/PASPv112n771
%J-631
%T V803 Centauri: A Helium-rich Dwarf Nova.
%A Patterson, Joseph (1)(2)
%A Walker, Stan (3)
%A Kemp, Jonathan (1)(2)(4)
%A O'Donoghue, Darragh (5)
%A Bos, Marc (6)
%A Stubbings, Rod (7)
%B We report 1992-1999 photometry of the helium-rich cataclysmic variable
   V803 Centauri. In its high brightness state at V=13, the star shows a strong
   periodic signal with P=1618 s; this resembles the superhumps associated with
   many dwarf novae. However, it is unusual because the superhump appears to
   endure through all brightness states, including the very faint state at V=17.
   The star also becomes occasionally stuck in a ``cycling state'', in which the brightness
   varies in the range 13.4-14.5, with a period of 22+/-1 hr. This appears to
   be the recurrence pattern of ``normal'' dwarf nova outbursts. Thus the underlying physics
   is probably that of a dwarf nova, but with an accretion disk dominated by
   helium. Reckoned as a dwarf nova, V803 Cen presents an interesting test for
   accretion disk theory, because it appears to display two timescales for eruption
   recurrence: 0.94 day at V=14.5 and ~5 days at V=17.2. This is roughly consistent
   with the general idea that recurrence time scales inversely with accretion rate.
%K Stars: Binaries: Close
%K Stars: Novae, Cataclysmic Variables
%K Stars: Individual: Constellation Name: V803 Centauri
%I (1) Department of Astronomy, Columbia University, 550 West 120th Street,
   New York, NY 10027; (jop@astro.columbia.edu).
%I (2) Biosphere 2 Observatory, Columbia University, 32540 South Biosphere Road,
   Oracle, AZ 85623; (jonathan@astro.bio2.edu).
%I (3) Center for Backyard Astrophysics (Awanui), Post Office Box 173, Awanui 0552,
   New Zealand; (astroman@voyager.co.nz).
%I (4) Visiting Astronomer, Cerro Tololo Inter-American Observatory, National
   Optical Astronomy Observatories, which is operated by the Association of
   Universities for Research in Astronomy (AURA), Inc., under cooperative agreement
   with the National Science Foundation.
%I (5) South African Astronomical Observatory, Post Office Box 9, Observatory 7935,
   Cape Town, South Africa; (dod@saao.ac.za).
%I (6) Center for Backard Astrophysics (Otahuhu), Mount Molehill Observatory, 83a
   Hutton Street, Otahuhu, Auckland, New Zealand; (molehill@ihug.co.nz).
%I (7) 19 Greenland Drive, Drouin 3818, Victoria, Australia; (stubbo@qedsystems.com.au).

%R 2000PASP..112..632R
%F ori/PASPv112n771
%J-641
%T Outburst Characteristics in the Dwarf Nova SU Ursae Majoris.
%A Rosenzweig, P. (1)
%A Mattei, J.A. (2)
%A Kafka, S. (3)
%A Turner, G.W. (3)
%A Honeycutt, R.K. (3)
%B The 1973-1999 {\em V}-band light curve from AAVSO visual estimates and
   RoboScope CCD exposures is examined to study the systematic properties of
   normal outbursts and superoutbursts in this prototype of the SU UMa-type
   dwarf novae. A number of the outbursts' correlations previously reported
   in VW Hyi and in SU UMa are not present in these data. Several lines of evidence
   suggest that, during this 26 year interval, variations in the mass-transfer
   rate served to obscure some of the expected correlations. The M{dot} variation apparently
   caused a nearly complete cessation of outbursting in 1980-1983. We do find
   a correlation of the time since the last superoutburst with the mean brightness
   in the interval since the last superoutburst, supporting the notion that
   superoutbursts are a disk-initiated phenomenon that occurs when the gas remaining
   in the disk after each normal outburst has accumulated to some critical value.
%K Stars: Novae, Cataclysmic Variables
%K Stars: Individual: Constellation Name: SU Ursae Majoris
%I (1) Universidad de Los Andes, Facultad de Ciencias, Departamento de F\'isica,
   GAT-CAT, M\'erida 5101-A, Venezuela; and Indiana University, Astronomy Department,
   Bloomington, IN 47405; (patricia@ciens.ula.ve).
%I (2) American Association of Variable Star Observers, 25 Birch Street, Cambridge,
   MA 02138-1205.
%I (3) Indiana University, Astronomy Department, Bloomington, IN 47405.

%R 2000PASP..112..642C
%F ori/PASPv112n771
%J-647
%T V529 Coronae Austrinae: An RV Tauri Variable of Type RVb(1).
%A Cieslinski, D.
%I Divis\~ao de Astrof\'isica, Instituto Nacional de Pesquisas Espaciais, CP 515,
   12201-970 S\~ao Jos\'e dos Campos, Brazil; (deo@das.inpe.br)
%A Steiner, J.E.
%I Laborat\'orio Nacional de Astrof\'isica (LNA/CNPq), CP 21, 37500-000 Itajub\'a,
   Brazil; and Instituto Astron\^omico e Geof\'isico, Universidade de S\~ao Paulo,
   CP 9638, 01065-970 S\~ao Paulo, Brazil; (steiner@lna.br)
%A Jablonski, F.J.
%A Hickel, G.R.
%I Divis\~ao de Astrof\'isica, Instituto Nacional de Pesquisas Espaciais, CP 515,
   12201-970 S\~ao Jos\'e dos Campos, Brazil; (chico@das.inpe.br), (hickel@das.inpe.br)
%B We present an analysis of the photometric data on V529 CrA. The data include
   published photographic data as well as our own {\em UBV}({\em RI})_C_ measurements.
   Two dominant modulations with periods of 23.571 and 761.5 days are present
   in the light curve. The double of the 23.571 day period (47.142 days) shows
   the alternating deep/shallow minima behavior of the RV Tauri class of variables,
   while the presence of a longer modulation indicates a classification in the
   photometric subclass RVb. Medium-resolution optical spectroscopy is also presented.
%K stars: individual (RV Tauri)
%K stars: individual (\objS{V* V529 CrA}{V529 Coronae Austrinae})
%I (1) Based partially on observations made at Laborat\'orio Nacional de Astrof\'isica/CNPq,
   Brazil, and Cerro Tololo Inter-American Observatory (CTIO), Chile.

%R 2000PASP..112..648G
%F ori/PASPv112n771
%J-690
%T Narrow Diffuse Interstellar Bands: A Survey with Precise Wavelengths.
%A Galazutdinov, G.A.
%I Special Astrophysical Observatory, Nizhnij Arkhyz 357147, Russia; (gala@sao.ru)
%A Musaev, F.A.
%I Special Astrophysical Observatory, Nizhnij Arkhyz 357147, Russia; (faig@sao.ru)
%A Kre{lstrok}owski, J.
%I Nicolaus Copernicus University, Center for Astronomy, Gagarina 11, Pl-87-100
   Toru{nacute}, Poland; (jacek@astri.uni.torun.pl) and
%A Walker, G.A.H.
%I Physics and Astronomy Department, University of British Columbia, Vancouver,
   BC V6T 1Z4, Canada; (walker@astro.ubc.ca)
%B We present an atlas of 271 diffuse interstellar bands (DIBs) between 4460
   and 8800 {AA} based on echelle spectra (R=45,000), of which more than 100 are
   new DIBs discovered in this survey. The atlas is restricted mostly to narrow features,
   and we describe the tests for an interstellar origin. The rest wavelength
   of each DIB was determined in a high-quality composite spectrum of the star
   HD 23180 using the interstellar Na I (D1 and D2) lines to establish the radial
   velocity of the single intervening cloud. DIB wavelengths are quoted to 0.01
   {AA} and are probably accurate to ~0.1 {AA}. Other, weak DIBs found in the spectra
   of heavily reddened stars are included with a lower wavelength precision.
%K ISM: Dust, Extinction
%K ISM: Abundances
%K ISM: General
%K ISM: Lines and Bands

%R 2000PASP..112..691Y
%F ori/PASPv112n771
%J-702
%T Calibration of the BATC Survey: Methodology and Accuracy.
%A Yan, Haojing (1)(2)(3)
%A Burstein, David (1)
%A Fan, Xiaohui (2)(4)
%A Zheng, Zhongyuan (2)(5)
%A Chen, Jiansheng (2)(5)
%A Byun, Yong-Ik (6)(7)
%A Chen, Rui (2)(5)
%A Chen, Wen-ping (6)
%A Deng, Licai (1)(2)(5)
%A Deng, Zugan (5)(8)
%A Fang, Li Zhi (9)
%A Hester, Jeff J. (1)
%A Jiang, Zhaoji (2)(5)
%A Li, Yong (1)
%A Lin, Weipeng (2)(5)
%A Lu, Phillip (10)
%A Shang, Zhaohui (2)(5)(11)
%A Su, Hongjun (2)
%A Sun, Wei-hsin (6)
%A Tsay, Wean-shun (6)
%A Windhorst, Rogier A. (1)
%A Wu, Hong (2)(5)
%A Xia, Xiaoyang (3)(5)
%A Xu, Wen (1)(2)
%A Xue, Suijian (2)(5)
%A Zheng, Zheng (2)(5)
%A Zhu, Jin (2)(5)
%A Zou, Zhenlong (2)(5)
%B We describe in detail the extinction correction procedures used for
   the Beijing-Arizona-Taiwan-Connecticut Sky Survey (BATC Survey). The survey
   covers the spectral range 3200-9900 {AA} by utilizing a set of 15 intermediate-band filters.
   These filters are specifically designed to exclude most of the bright and
   variable night-sky emission lines. We also present extinction coefficients
   for the filter passbands for typical photometric nights at the Xinglong Observing
   Station, Beijing Astronomical Observatory (where the observations of the
   survey are being carried out). Time-dependent, low-amplitude (~1%), nightly
   extinction variation has been observed. Such variation is demonstrably independent
   of filter bandpass and air mass, with amplitudes ranging from ~0.01 to ~0.03
   mag. The variation is plausibly caused by slowly varying (at ~1%) atmospheric
   extinction, possibly related to changes in air pressure/temperature/humidity that
   occur during the night. An iterative fitting scheme has been developed to
   take this time-varying component into account. We conclude that the survey
   can achieve its stated observational goal, namely, an absolute photometric
   calibration that is tied to the AB_{nu}_ system to an accuracy of 1% in all
   filters.
%K Site Testing
%K Surveys
%I (1) Department of Physics and Astronomy, Box 871504, Arizona State University,
   Tempe, AZ 85287-1504; (david.burstein@asu.edu).
%I (2) Beijing Astronomical Observatory, Chinese Academy of Sciences, Beijing 100012,
   China.
%I (3) Department of Physics, Tianjin Normal University, China.
%I (4) Princeton University Observatory, Princeton, NJ 08544.
%I (5) Beijing Astrophysics Center (BAC), Beijing, 100871, China. BAC is
   jointly sponsored by the Chinese Academy of Sciences and Peking University.
%I (6) Institute of Astronomy, National Central University, Chung-Li, Taiwan,
   China.
%I (7) Center for Space Astrophysics and Department of Astronomy, Yonsei University,
   Seoul, 120-749, Korea.
%I (8) Graduate School, Chinese Academy of Sciences, Beijing 100080, China.
%I (9) Department of Physics, University of Arizona, Tucson, AZ 85721.
%I (10) Department of Physics and Astronomy, Western Connecticut State University,
   Danbury, CT 06810.
%I (11) Department of Astronomy, University of Texas at Austin, Austin,
   TX 78712.

%R 2000PASP..112..703R
%F ori/PASPv112n771
%J-710
%T Cosmic-Ray Rejection by Linear Filtering of Single Images.
%A Rhoads, James E. (1)
%I Kitt Peak National Observatory, 950 North Cherry Avenue, Tucson, AZ 85719;
   (jrhoads@noao.edu)
%B We present a convolution-based algorithm for finding cosmic rays in
   single well-sampled astronomical images. The spatial filter used is the point-spread
   function (approximated by a Gaussian) minus a scaled delta function, and
   cosmic rays are identified by thresholding the filtered image. This filter
   searches for features with significant power at spatial frequencies too high
   for legitimate objects. Noise properties of the filtered image are readily
   calculated, which allows us to compute the probability of rejecting a pixel
   not contaminated by a cosmic ray (the false alarm probability). We demonstrate
   that the false alarm probability for a pixel containing object flux will
   never exceed the corresponding probability for a blank-sky pixel, provided we
   choose the convolution kernel appropriately. This allows confident rejection
   of cosmic rays superposed on real objects. Identification of multiple-pixel
   cosmic-ray hits can be enhanced by running the algorithm iteratively, replacing
   flagged pixels with the background level at each iteration.
%K Techniques: Image Processing
%I (1) Current address: Space Telescope Science Institute, 3700 San Martin Drive,
   Baltimore, MD 21218; (rhoads@stsci.edu).

%R 2000PASP..112..711K
%F ori/PASPv112n771
%J-715
%T Three-Phase Switching with m-Sequences for Sideband Separation in Radio Interferometry.
%A Keto, Eric
%I Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138;
   (keto@cfa.harvard.edu)
%B Orthogonal sequences known as m-sequences can be used in place of Walsh
   functions in phase switching and sideband separation in cross-correlation
   interferometers. Functions based on three-character m-sequences may be advantageous
   because they may provide a larger set of mutually orthogonal modulation and
   demodulation functions, and hence support a larger number of antennas for
   a given sequence length, than allowed by other orthogonal sequences such
   as Walsh functions. The reason for this advantage is that if the demodulation functions
   are formed from the differences of the three-character m-sequence modulation
   functions, then because the m-sequences obey an addition rule whereby sums
   or differences of m-sequences are also m-sequences, the demodulation functions
   are also members of the original orthogonal set. In a complete set of sequences,
   all the differences are of course duplicates of the original sequences. However, certain
   subsets of sequences have differences which are not members of the subset,
   and these subsets can be used to form modulation and demodulation functions
   which have both the desired uniqueness and orthogonality properties. While
   it is not obvious how to select the subsets, heuristic methods seem reasonably successful.
%K Instrumentation: Interferometers

%R 2000PASP..112..716J
%F ori/PASPv112n771
%J-732
%T The University of Hawaii 2.2 Meter Fast Tip-Tilt Secondary System.
%A Jim, Kevin T.C.
%A Pickles, Andrew J.
%A Yamada, Hubert T.
%A Graves, J.Elon
%A Stockton, Alan
%A Northcott, Malcolm J.
%A Young, Tony
%A Cowie, Lennox L.
%A Luppino, Gerard A.
%A Thornton, Robert J.
%A Kupke, Renate
%A Sousa, Edward
%I Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu,
   HI 96822; (jim@ifa.hawaii.edu), (pickles@ifa.hawaii.edu), (yamada@ifa.hawaii.edu),
   (graves@ifa.hawaii.edu), (stockton@ifa.hawaii.edu), (northcott@ifa.hawaii.edu),
   (tyoung@ifa.hawaii.edu), (cowie@ifa.hawaii.edu), (ger@ifa.hawaii.edu), (thornton@ifa.hawaii.edu),
   (kupke@ifa.hawaii.edu), (sousa@ifa.hawaii.edu)
%A Cavedoni, Charles P.
%I Joint Astronomy Centre, 660 North A'ohoku Place, University Park, Hilo, HI 96720;
   (Chas.Cavedoni@jach.hawaii.edu)
%A Keller, Timothy J.
%I Electroglas, Inc., 3001 Coronado Drive, Santa Clara, CA 95054; (TKeller@Electroglas.com)
%A Nakamura, Wesley
%I KLA-Tencor Corporation, 160 Rio Robles, San Jose, CA 95134; (wnakamu@falcon.kla-tencor.com)
%A Metzger, M.R.
%I Department of Astronomy, California Institute of Technology, Pasadena, CA
   91125; (mrm@astro.caltech.edu)
%B Using a new f/31 secondary on a tip-tilt platform, we have built an
   image-stabilization system which has been used regularly for astronomical
   imaging and spectroscopy on the University of Hawaii 2.2 m telescope. Diffraction-limited
   cores of stellar point-spread functions are achieved in near-infrared imaging,
   with Strehl ratios as high as 0.47. {\em K}-band images with 0".3 FWHM resolution
   (without deconvolution) are routinely obtained. The construction, operation,
   and capability of the current system are described, a summary of recent scientific
   findings is presented, and future improvements are outlined.
%K Instrumentation: Detectors
%K Instrumentation: Miscellaneous

%R 2000PASP..112..733O
%F ori/PASPv112n771
%J-741
%T Faint Emission Lines in the Blue and Red Spectral Regions of the Night Airglow(1).
%A Osterbrock, Donald E.
%A Waters, Richard T.
%I University of California Observatories/Lick Observatory, Department of Astronomy
   and Astrophysics, University of California, Santa Cruz, CA 95064; (don@ucolick.org),
   (waters@ucolick.org)
%A Barlow, Thomas A.
%I Infrared Processing and Analysis Center, California Institute of Technology,
   Pasadena, CA 91125; (tab@ipac.caltech.edu) and
%A Slanger, Tom G.
%A Cosby, Philip C.
%I Molecular Physics Laboratory, SRI International, Menlo Park, CA 94025; (slanger@mplvax.sri.com),
   (cosby@mplvax.sri.com)
%B Co-added night-sky spectra, obtained as by-products of exposures with
   the Keck I 10 m telescope on Mauna Kea and the HIRES high-resolution echelle
   spectrograph over a period of approximately 4 years, all completely independent
   of similar data published earlier, are presented. The new data total over
   150 hours exposure in one order (5505-5625 {AA}), more than 100 hours in 16
   orders, and more than 50 hours in all orders in the spectral range 3923-7853 {AA}
   and include smaller numbers of hours over the entire range 3618-9023 {AA}. From
   these data, co-added in the red region to the previously published data,
   two additional Meinel OH bands, 8-1 and 7-0, were found in emission in the
   spectrum of the night airglow, the presence of the 6-0 band was confirmed,
   and numerous lines of the 10-4 and 10-5 bands were detected. Three Hg I light-pollution
   lines were detected as weakly present in the Mauna Kea night sky. Three other
   predicted Meinel bands are too faint and still were not detected with certainty.
   Similarly, neither OD nor the Rb I or Cs I resonance lines were seen. Upper
   limits were set on the latter, which are consistent with their abundance
   ratios to K and the observed strength of the K I resonance line {lambda}7699,
   if the excitation mechanisms of all these three alkali atoms were equally
   effective. Brief references are given to other papers in press based on these
   new spectral data and to other work in progress on identifications of many
   additional O_2_ bands in the spectrum of the night airglow. A table summarizes
   all the identifications of all OH emission bands in the spectrum of the night
   airglow, in all spectral regions.
%K Earth
%K ISM: Lines and Bands
%K Physical Data and Processes
%I (1) Lick Observatory Bulletin 1391. Based on observations obtained at
   the W. M. Keck Observatory, which is operated by the California Institute
   of Technology and the University of California.

%R 2000PASP..112..742M
%F ori/PASPv112n771
%J-743
%T Investigation of Herbig Ae/Be Stars in the Near-Infrared with a Long-Baseline
   Interferometer. (Dissertation Summary).
%A Millan-Gabet, R.
%I Present address: Harvard-Smithsonian Center for Astrophysics, 60 Garden Street,
   Cambridge, MA 02138; (rmillan@cfa.harvard.edu)Thesis work conducted at University
   of Massachusetts at AmherstPh.D. thesis directed by F. P. Schloerb; Ph.D.
   degree awarded 1999
%K Stars: Circumstellar Matter
%K Dissertation Summaries
%K Stars: Early-Type
%K Stars: Pre-Main-Sequence
%K Instrumentation: Detectors
%K Techniques: Interferometric