new developments in array technology …978-94-011-0383...1nfernational astronomical union union...

NEW DEVELOPMENTS IN ARRAY TECHNOLOGY AND APPLICAnONS

1NfERNATIONAL ASTRONOMICAL UNION

UNION ASTRONOMIQUE INfERNATIONALE

NEW DEVELOPMENTS IN ARRA Y TECHNOLOGY

AND APPLICATIONS PROCEEDINGS OF THE 167TH SYMPOSIUM OF THE

INTERNATIONAL ASTRONOMICAL UNION, HELD IN THE HAGUE, THE NETHERLANDS, AUGUST 23-27, 1994

EDITEDBY

A. G. DA VIS PHILIP Union College ami the Institute for Space Observations

KENNETH A. JANES Boston University

and

ARTHUR R. UPGREN Van Vleck Observatory, Wesleyan University

SPRINGER-SCIENCE+BUSINESS MEDIA, B.V.

A C.I.P. Catalogue record for this book is available from the Library of Congress.

ISBN 978-0-7923-3640-2 ISBN 978-94-011-0383-1 (eBook) DOI 10.107/978-94-011-0383-1

Printed on acid-free paper

Alt Rights Reserved ©1995 Springer Science+Business Media Dordrecht

Originally published by Kluwer Academic Publishers in 1995

No part of the material protected by this copyright notice may be reproduced or utilized in any form or by any means, electronic or mechanical including photocopying, recording or by any information storage and retrieval system, without written permission

from the publisher.

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Table of Contents

Preface

Section I - Review Papers

INTRODUCTION

A. G. Davis Philip

ARRAY DETECTORS AND INSTRUMENTS FOR THE ESO VLT

Sandro D'Odorico

DESIGN AND FABRICATION OF LARGE CCDs FOR THE KECKOBSERVATORY DEIMOS SPECTROGRAPH

R. J. Stover, W. E. Brown, D. K. Gilmore andM. Wei

SCIENTIFIC CCD PROSPECTS FOR 1994 AND BEYOND

Paul R. Jorden and A. P. Oates

NEW DEVELOPMENTS IN CCD TECHNOLOGY FOR THE UV-EUVSPECTRAL RANGE

Giovanni Bonanno

CCD CONTROLLERS

Robert W. Leach

CCDs IN ACTIVE ACQUISITION SYSTEMS

A. Blecha

CCD DEVELOPMENT ACTIVITIES AT ESO

O.Iwert

INFRARED ARRAY DETECTORS: PERFORMANCE AND PROSPECTS

Ian S. McLean

xv

3

9

19

27

39

49

57

67

69

viii

THE LICK OBSERVATORY TWO MICRON CAMERA

K. Gilmore, D. Rank and P. Temi

INFRARED ARRAYS AT THE EUROPEAN SOUTHERN OBSERVATORY

79

G. Finger, G. Nicolini, P. Biereichel, M. Meyer andA. F. M. Moorwood 81

THE IMPACT OF INFRARED ARRAY TECHNOLOGY ON ASTRONOMY

Giovanni G. Fazio

MONOLITHIC Si BOLOMETER ARRAYS: DETECTORS FOR FARINFRARED AND SUBMILLIMETER DETECTION

Harvey Moseley

OBSERVATIONAL CONCERNS AND TECHNIQUES FOR HIGH­BACKGROUND MID-INFRARED (5 - 20 micron) ARRAY IMAGING

Daniel Y. Gezari

AN INFRARED CAMERA BASED ON A LARGE PtSi ARRAY

I. S. Glass, K. Sekiguchi and Y. Nakada

PtSi IR ARRAY IN MOSAIC CONFIGURAnON

Munetaka Ueno, Fumiaki Tsumuraya andYoshihiro Chikada

CCD PHOTOMETRY - PRESENT AND FUTURE

Alistair R. Walker

CCD PHOTOMETRY: SOME BASIC CONCERNS

C. Sterken

CHOOSING FILTERS TO MAKE CCD PHOTOMETRY TRANS­FORMABLE TO OTHER DETECTORS

Andrew T. Young

93

95

97

109

117

123

131

145

ix

AUTOMATED CCD SCANNING FOR NEAR EARTH ASTEROIDS

Robert Jedicke

CCD TIME SERIES PHOTOMETRY OF ASTRONOMICAL SOURCES

Steve B. Howell

HIGH PRECISION STELLAR PHOTOMETRY WITH CCDs. 1.

A. J. Penny

HIGH PRECISION STELLAR PHOTOMETRY WITH CCDs. II.

Michael S. Bessell

PRECISION DIFFERENTIAL CCD PHOTOMETRY

L. A. Balona

157

167

173

175

187

ARRAY POLARIMETRY AND OPTICAL-DIFFERENCING PHOTOMETRY

J. Tinbergen

COSMIC RAY EVENTS AND NATURAL RADIOACTIVITY INCCD CRYOSTATS

Ralph Florentin-Nielsen, Michael J. Andersenand Sven P. Nielsen

MOCAM: A 4k X 4k CCD MOSAIC FOR THE CANADA-FRANCE­HAWAll TELESCOPE PRIME FOCUS

J. C. Cuillandre, Y. Melliers, R. Murowinski,D. Crampton, G. Luppino and R. Arsenault

ECHELLE SPECTROSCOPY WITH A CCD AT LOW SIGNAL-TO­NOISE RATIO

Didier Queloz

NICMOS3 DETECTOR 'FOR SPECTROSCOPY

L. Vanzi, A. Marconi and S. Gennari

SPECTRAL CLASSIFICATION WITH ARRAY DETECTORS

c. J. Corbally

197

207

213

221

231

241

x

SPECTROSCOPIC OBSERVATIONS OF SOLAR SYSTEM OBJECTS:PUSHING THE LIMITS

Anita L. Cochran

"VA-ET-VENT" ("BACK-AND-FORTH") CCD SPECTROSCOPY:A NEW WAY TO INCREASE THE LIMITING MAGNITUDE OFVERY LARGE TELESCOPES

G. Soucail, j. C. Cuillandre, J. P. Picatand B. Fon

SOME PROBLEMS OF WIDE-FIELD ASTROMETRY WITH A SHORT­FOCUS CCD ASTROGRAPH

1. S. Guseva

A DUAL CCD MOSAIC CAMERA SYSTEM SEARCHING FORMASSIVE COMPACT HALO OBJECTS (MACHOs)

Kern H. Cook

MULTI-FIBER SPECTROSCOPY WITH WIDE-FIELD TELESCOPES

F. G. Watson

PERFORMANCE OF A 2048 x 2048 PIXEL THREE-SIDE­BUTTABLE CCD DESIGNED FOR LARGE FOCAL PLANESIN ASTRONOMY

J. A. Coniula

CCD MOSAIC DEVELOPMENT FOR LARGE OPTICAL TELESCOPES

G. A. Luppino, M. R. Mezger andS. Miyazaki

HIGHLIGHTS OF IAU SYMPOSIUM No. 167

Sandro D'Odorico

251

263

275

285

287

295

297

309

xi

Section II - Poster Papers

THE TRANSPUTER BASED CCD CONTROLLER AT ESO

Roland Reiss

DETECTOR CONTROLLERS FOR THE GALILEO TELESCOPE: APROGRESS REPORT

317

G. Bonanno, P. Bruno, R. Consentino, F. Bortoletto,M. D'Alessandro, D. Fantinel, A. Balesstra andP. Marcucci 319

THE RUTHERFORD-SAAO CCD CONTROLLERS AND THEIRAPPLICATIONS

I. S. Glass, D. B. Carter, G. F. Woodhouse,N. A. Waltham and G. M. Newton

CCD IMAGERS WITH ENHANCED UV SENSITIVITY FOR INDUSTRIALAND SCIENTIFIC APPLICATIONS

321

G. I. Vishnevsky, M. G. Vydrevich, L. Yu. Lazovsky,V. G. Kossov and S. S. Tataushchikov 323

THE LARGE-FIELD BRIGHT-STAR HIGH-PRECISION CCDPHOTOMETER OF BAO

Shiyang Jiang

EFFECTS OF SHUTTER TIMING ON CCD PHOTOMETRY

D. Galadi-Enriquez, C. Jordi and E. Trullols

ASTRONOMICAL APPLICATIONS OF CCDs IN HUNGARY: THEFIRST STEPS AND FUTURE PLANS

G. Szecsenyi-Nagy

A SIMPLE CCD-SYSTEM FOR SECONDARY ALIGNMENT OF THESPECTRUM-UV SPACE TELESCOPE

325

327

329

V. Didkovsky, N. V. Steshenko, P. I. Borzyakand A. I. Dolgushin 331

xii

THE MODERNIZATION OF THE PULKOVO PHOTOGRAPHIC(PHOTOELECTRIC) VERTICAL CIRCLE BY A CCD ARRAY

G. A. Goncharov, B. K. Bagildinsky, E. V. Kornilov,D. D. Polojentsev, K. V. Rumyantsev and V. D. Shkutov 333

A NEW OCULAR MICROMETER FOR THE MAHIS

T. R. Kirian, V. S. Korepanov and V. M. Grozdilov 335

PbS AND CCD ARRAY AUTOCOLLIMATION MICROMETERSFOR THE INFRARED MERIDIAN CIRCLE

V. N. Yershov

THE NOAO CCD CONTROLLER- ARCON

Alistair R. Walker

INTENSIFIED ELECTRON-BOMBARDED CCD IMAGES FORINDUSTRIAL AND SCIENTIFIC APPLICATIONS

337

339

I. Dalinenko, G. Vishnevsky, V. Kossov, L. Lasovsky,G. Kuzmin and A. Malyarov 341

THE CCDs AT ESO: A SYSTEMATIC TESTING PROGRAM

T. M. C. Abbott

DEVELOPMENT OF A 7000 x 4000 PIXEL MOSAIC CCD CAMERA

343

Nobunari Kashikawa, Masafumi Yagi, Naoki Yasuda,Sadanori Okamura, Kazuhiro Shimasaku, MamoruDoi and Maki Sekiguchi 345

THE FEASIBILITY OF A CCD FOR AN ASTROMETRIC REFRACTOR

A. R. Upgren, Alice Morales, Jose Herrero, J. W.Griese, III, J. M. Vincent and John T. Lee 347

STELLAR POSITIONS FROM CCD IMAGES

A. R. Upgren, C. Abad and J. Stock 349

xiii

ON THE ACCURACY OF CCD AND PHOTOGRAPHICOBSERVAnONS OF ASTEROIDS AND THEIR CURRENTORBIT DETERMINAnONS

O. P. Bykov

ON THE PROBLEM OF STANDARD FIELDS FOR CCD ASTROMETRY

I. S. Guseva

COMBINED VISUAL AND NEAR-IR DIGITAL PHOTOMETRY: THEVERY YOUNG CLUSTER WESTERLUND 2

M. D. Guarnieri, M. Gai, G. Massone,M. G. Lattanzi, U. Munari and A. Moneti

A DUAL CCD MOSAIC CAMERA SYSTEM SEARCHING FORMASSIVE-COMPACT HALO OBJECTS (MACHOs)

Kern H. Cook

JHK PHOTOMETRY OF EXTRAGALACTIC SOURCES USING ANINFRARED ARRAY CAMERA

I. S. McLean, T. Liu and H. Tepliz

PRECISION CCD PHOTOMETRY OF THE HORIZONTAL BRANCH

A. G. Davis Philip

CCD PHOTOMETRY OF THE M 67 CLUSTER IN THE VILNIUSPHOTOMETRIC SYSTEM

R. Boyle, V. Straizys, F. Vrba,F. Srnriglio and A. Dasgupta

ESTIMAnON OF THE ERRORS INVOLVED IN THE INTENSITYMEASUREMENT OF LOW SiN RATIO EMISSION LINES

Claudia Rola and Didier Pe!at

EEV AND ELECTRON CORP. VIRTUAL PHASE CCDs IN THENEAR IR REGION, He A 10830 A

351

353

355

357

359

361

363

365

A. G. Shcherbakov, Z. A. Shcherbakova, I. Ilyin andI. Tuuorninen 367

xiv

STELLAR PHOTOMETRY WITH A PERFECT CCD

Bjarne Thomsen and Frank Grondahl Jensen

APPLICAnONS OF A REALISTIC MODEL FOR CCD IMAGING

Steve B. Howell and William J. Merline

3D: THE NEW NEAR-INFRARED FIELD IMAGING SPECTROMETER

369

371

L. E. Tacconi-Garmen, L. Weitzel, M. Cameron, S.Drapatz, R. Genzel, A. Krabbe, H. Kroker andN. Thatte 373

TECHNICAL CCD SYSTEMS FOR THE ESO VERY LARGE TELESCOPE

J. Erich

POSTER DISCUSSIONS

INDEX

NAME INDEX

OBJECT INDEX

SUBJECT INDEX

375

377

381

383

388

390

PREFACE

At the XIX General Assembly in Bueonos Aires it was announced that the format offuture General Assemblies would be changed and that Symposia would be held concurrentlywith the Assemblies and not as satellite meetings as had been the custom previously. On theflight back to New York I thought about what topic might be good for a meeting at the XXIIGeneral Assemby. The most important topic to me was the new technology that has developedas a result of the invention of CCDs and Arrays. CCD and Array detectors have become thedetectors of choice at optical observatories over the world. Direct imaging, photometry andspectroscopy are all vastly improved as a result. Observations can be made of faint and crowdedobjects that one could not even consider measuring before the advent of the CCD. Theaccuracy of photometric and spectroscopic measures has increased dramatically. Small telescopescan now do research projects that used to be possible only on the larger telescopes. I thoughtthat the General Assembly in The Hague would be an excellent forum for the meeting andwould have a great potential for interactions between the members of many differentcommissions, astronomers working with the devices and people who design and manufacturethe devices.

Commission 45 (Stellar Classification) was the official commission sponsor of the meeting.Co-sponsors were Commissions 8, 9, 15, 16, 20, 24, 25, 28, 29, 30, 37 and 42. The institutionsthat sponsored the meeting were:

The Institute for Space ObservationsThe European Southern ObservatoryUnion CollegeVanVleck Observatory

Schenectady, New YorkGarching, GermanySchenectady, New YorkMiddletown, Connecticut.

The Scientific Organizing Committee was composed of the following:

A. G. Davis PhilipSandro D'OdoricoMichael BessellAndre BlechaRoberto BonannoEdward BowellMartin CullumLief HelmerHugo LevatoDavid MonetLloyd RobinsonMarcello RodonoRichard WestAndy Young

ChairCo-ChairAustraliaSwitzerlandItalyUSAGermanyDenmarkArgentinaUSAUSAItalyGermanyUSA

The Local Organizing Committee was composed of the following:

Jaap TinbergenChristiaan Sterken

xv

ChairBelgium

xvi

No List of Participants is available for printing in the proceedings volume. The IAUpresented a list of 300 astronomers who had indicated their interest in attending the meetingbut we have no way of determining which people actually were present.

Special thanks are due Mary Bongiovanni who collected the discussion sheets, typed themup and then passed them back to speakers for corrections. The discussions were in almost finalform by the end of the meeting. The IAU Executive Committee assigned some Dutchastronomers to help us in running the daily affairs of the meeting. They were a great help andI want to thank Marco Kouwenhoven, Frank MoIster, Nick Schutgens, Robert van Eysbergenand Pieter Veen for their fine work. Sandro D'Odorico was a great help in organizing themeeting and was in charge of the European side of things. The European Southern Observatorysupported the meeting financially and also printed abstract booklets, containing abstracts of oraland poster papers, for distribution to participants. lmmo Appenzeller, who opened the meetingwith a short speech of welcome, gave very useful advice in the early stages of planning for themeeting. My two co-editors found many things to correct, from grammer, spelling to problemswith references. Kristina Philip also helped as a proofreader.

The final discussion was prepared at the Moletai Observatory in Lithuania and mailed fromthere to authors. Papers were submitted on floppy disks or sent via email to Schenectady.WordPerfect 6.0b was used to edit the ASCII versions of the submitted papers. Proofs werewere sent back to each author and then authors emailed their corrections back to Schenectady.This cooperation between the editors and authors is a necessary part of preparing an accuratetranscript of the meeting and all who participated in the effort are thanked for their help.

The cover photo shows a CAD view of part of the new ESO detector head (taken fromD'Odorico's paper, page 15).

SchenectadyApril, 1995

A. G. Davis Philip

LIST OF CONTRIBUTORS

T.M.C. AbbottESOCasilla 19001Santiago 19ChileTABBOTT@ESO.ORG

L.A. BalonaSouth African Astronomical ObservatoryP.O. Box 9Observatory7935 CapetownSouth AfricaLAB@MV.SAAO.AC.zA

Michael S. BessellMount Stromlo and Siding Spring ObservatoriesWeston Creek PO, ACT 2611AustraliaBESSELL@MIDGET.ANU.EDU.AU

A. BlechaObservatoire de Geneve51 Ch. des Mailettes1290 SauvernySwitzerlandBLECHA@OBS.UNIGE.CH

Giovanni BonannoOsservatorio Astrofisico di CataniaViale A. Doria 692125 CataniaItalyGBONANNO@CT.ASTRO.IT

R. BoyleVatican Observatory GroupSteward ObservatoryUniversity of ArizonaTucson, Arizona 85721U.S.A.RBOYLE@AS.ARIZONA.EDU

O.P. BykovPulkovo Observatory196140 St PetersburgRussiaOBYK@GOARAN.SPB.SU

xvii

Anita L. CochranUniversity of TexasMcDonald ObservatoryAustin, Texas 78712U.S.A.ANITA@ZINFANDEL.AS.UTEXAS.EDU

Kern H. CookLawrence Livermore National LaboratoryMS L-40 I PO Box 808Livermore, California 93405U.S.A.KCOOK@IMAGER.LLNL.GOV

C.J. CorballyVatican ObservatorySteward ObservatoryUniversity of ArizonaTucson, Arizona 85721U.S.A.CCORBALLY@AS.ARIZONA.EDU

J.A. CortiulaThomson-CSF Semiconducteurs SpecifiquesBP 123F-38521 St EgreveFrance

J.e. CuillandreObservatoire Midi-PyreneesURA-CNRS 28514 Avenue E. BelinF-314oo ToulouseFranceCUILLAND@SRVDEC.OBS-MIP.FR

I. DalinenkoElectron Research InstituteSt PetersburgRussia

L.V. DidkovskyCrimean Astrophysical ObservatoryNauchny, CrimeaUkraineDIDKOVSKY@CRAO.CRIMEA.UA

xviii

J. EhrichJena-Optronik GmbHGtischwitzer Strasse 33D-07745 Jena-GtischwitzGermany

Giovanni G. FazioHarvard-Smithsonian Center for AstrophysicsCambridge, Massachusetts 02138U.S.A.FAZIO@CFA.HARVARD.EDU

G. FingerEuropean Southern ObservatoryGarching bei MiinchenGermanyGFINGER@ESO.ORG

Ralph Florentin-NielsenNiels Bohr Institute for AstronomyCopenhagen University ObservatoryCopenhagenDenmark

D. Galadf-EnrfquezDept. d'Astronomia i MeteorologiaUniversitat de BarcelonaAvda. Diagonal 647E-08028 BarcelonaSpainCARMEN@FACJNO.UB.ES

K. GilmoreLick ObservatorylUCO UCSCSanta Cruz, California 95064U.S.A.GILMORE@HELIOS.UCSC.EDU

1.S. GlassSouth African Astronomical ObservatoryP.O. Box 9Observatory7935 CapetownSouth AfricaISG@SAAO.AC.ZA

Daniel Y. GezariNASNGoddard Space Flight CenterCode 685Greenbelt, Maryland 20771U.S.A.GEZARI@STARS.GSFC.NASA.GOV

G.A. GoncharovPulkovo Observatory196140 St PetersburgRussiaGOSHA@GAORAN.SPB.SU

M.D. GuarnieriOsservatorio Astronomico di TorinoTorinoItalyMDGUARNIERI@TO.ASTRO.IT

1.S. GusevaPulkovo Observatory196140 St PetersburgRussiaISG@GAORAN.SPB.SU

Steve B. HowellPlanetary Science InstituteTucson, Arizona 85705U.S.A.HOWELL@PS1.EDU

O.IwertEuropean Southern ObservatoryGarching bei MiinchenGermanyOIWERT@ESO.ORG

Robert JedickeLunar and Planetary LaboratoryUniversity of ArizonaTucson, Arizona 85721U.SAJEDICKE@PIRL.LPL.ARIZONA.EDU

Shiyang JiangBeijing Astronomical ObservatoryBeijing 10080People's Republic of China

Paul R JordenRoyal Greenwich ObservatoryMadingly RoadCambridge, CB3 OEZU.K.PRJ@MAILAST.CAM.AC.UK

Nobunari KashikawaUniversity of TokyoBunkyo-kuTokyo 113JapanBKASHIK@CI.MTK.NAO.AC.JP

T.R KirianPulkovo Observatory196140 St PetersbrugRussiaKTR@GAORAN.SPB.SU

Robert W. LeachDepartment of AstronomySan Diego State UniversitySan Diego, California 02182U.S.A.LEACH@MINTAKA.SDSU.EDU

G.A. LuppinoInstitute for AstronomyUniversity of HawaiiHonolulu, Hawaii 96822U.S.A.GER@GALILEO.IFA.HAWAIl.EDU

Ian S. McLeanDepartments of Astronomy and PhysicsUCLALos Angeles, California 90024U.S.A.MCLEAN@BONNIE.ASTRO.UCLA.EDU

Harvey MoseleyLaboratory for Astronomy and Solar PhysicsGoddard Space Flight CenterGreenbelt, Maryland 20771U.S.A.MOSELEY@STARS.GSFC.NASA.GOV

Sandro D'OdoricoEuropean Southern ObservatoryGarching bei MiinchenGermanySDODORIC@ESO.ORG

AJ. PennyRutherford Appleton LaboratoryBuilding R25/R68Chilton, Didcot OXI I OQXU.K.AJP@STARLINK.RUTHERFORD.AC.UK

A.G. Davis Philip1125 Oxford PlaceSchenectady, New York 12308U.S.A.AGDP@GARUNION.EDU

Didier QuelozObservatoire de Geneve51 Ch. des Maillettes1290 SauvernySwitzerlandQUELOZ@SCSUN.UNIGE.CH

Roland ReissEuropean Southern ObservatoryGarching bei MiinchenGermanyRREISS@ESO.ORG

Claudia RolaDAEC, Observatoire de MeudonMeudonFranceROLA@GIN.OBSPM.FR

A.G. ShcherbakovCrimean Astrophysical ObservatoryNauchny, CrimeaUkraineSHERB@CRAO.CRIMEA.UA

G. SoucailObservatoire Midi-PyreneesURA-CNRS 28514 Avenue E. BelinF-314oo ToulouseFranceSOUCAIL@SRVDEC.OBS-MIP.FR

xix

xx

Christiaan SterkenIAAG, University of BrusselsBrusselsBelgiumCSTERKEN@ISI.VUB.AC.BE

Richard 1. StoverLick ObservatoryUniversity of CaliforniaSanta Cruz, California 95064U.S.A.RICHARD@UCSCLOA.UCSC.EDU

Gabor Szecsenyi-NagyDepartment of AstronomyEotvos Lonind UniversityLudovika ter 2H-1083 BudapestHungarySZENA@LUDENS.ELTE.HU

L.E. Tacconi-GarmanMax-Planck-Institut fUr Extraterrestrische

PhysikGarching bei MtinchenGermanyLOWEL%MPEI2@MPE.MPE-GARCHING.MPG.DE

Bjarne ThomsenInstitute of Physics and AstronomyAarhus UniversityNy MunkegadeDk-8000 Aarhus C.DenmarkBT@OBS.AAU.DK

Jaap TinbergenKapteyn SterrewachtMensingweg 20930 I KA RodenThe NetherlandsTlNBERGEN@KSW.RUG.NL

Munetaka UenoDepartment of Earth Science and AstronomyUniversity of TokyoTokyoJapanUENO@KYOHOU.C.U-TOKYO.AC.JP

A.R. UpgrenVan Vleck ObservatoryWesleyan UniversityMiddletown, Connecticut 06457U.S.A.AUPGREN@EAGLE.WESLEYAN.EDU

Leonardo VanziUniversita degli Studi di FirenzeFirenzeItalyVANZI@ARCETRLASTROJT

GJ. VishnevskyElectron Research InstituteSt PetersburgRussiaVISH@ISTA.SPB.SU

Alistair R. WalkerCerro Tololo Inter-American ObservatoryCasilla 603La SerenaChileAWALKER@NOAO.EDU

F.G. WatsonRoyal Greenwich ObservatoryCambridgeU.K.FGW@MAIL.AST.CAM.AC.UK

Y.N. YershovPulkovo Observatory196140 St PetersbrugRussiaYERSH@GAORAN.SPB.SU

Andrew T. YoungAstronomy DepartmentSan Diego State UniversitySan Diego, California 92182-0540U.S.A.ATY@MINTAKA.SDSU.EDU