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[email=TheEinstein@HomesearchforperiodicgravitationalwavesinLIGOS4data]TheEinstein@HomesearchforperiodicgravitationalwavesinLIGOS4data[/email]
16 16 16 2 2,55 32 20 41
B.Abbott, R.Abbott, R.Adhikari, P.Ajith, B.Allen, G.Allen, R.Amin, D.P.Anderson,
16 55 42 16 16 55 10
S.B.Anderson, W.G.Anderson, M.A.Arain, M.Araya, H.Armandula, P.Armor, Y.Aso,
40 15 2 1 16 8 16 18
S.Aston, P.Aufmuth, C.Aulbert, S.Babak, S.Ballmer, H.Bantilan, B.C.Barish, C.Barker,
18 43 54 43 43 17 16
D.Barker, B.Barr, P.Barriga, M.A.Barton, M.Bastarrika, K.Bayer, J.Betzwieser,
28 23 16 55 16 16 17
P.T.Beyersdorf, I.A.Bilenko, G.Billingsley, R.Biswas, E.Black, K.Blackburn, L.Blackburn,
54 18 17 19 16 16 56 55
D.Blair, B.Bland, T.P.Bodiya, L.Bogue, R.Bork, V.Boschi, S.Bose, P.R.Brady,
23 48 2 16 33 17 32
V.B.Braginsky, J.E.Brau, M.Brinkmann, A.Brooks, D.A.Brown, G.Brunet, A.Bullington,
44 2 32 45 43 24 24
A.Buonanno, O.Burmeister, R.L.Byer, L.Cadonati, G.Cagnoli, J.B.Camp, J.Cannizzo,
16 17 16 32 51 16 43 9
K.Cannon, J.Cao, L.Cardenas, T.Casebolt, G.Castaldi, C.Cepeda, E.Chalkley, P.Charlton,
16 40 6,1 8 32 43 7 50
S.Chatterji, S.Chelkowski, Y.Chen, N.Christensen, D.Clark, J.Clark, T.Cokelaer, R.Conte,
18 17 16 55 43 43 40
D.Cook, T.Corbitt, D.Coyne, J.D.E.Creighton, A.Cumming, L.Cunningham, R.M.Cutler,
33 15,2 7 32 1 32 46
J.Dalrymple, K.Danzmann, G.Davies, D.DeBra, J.Degallaix, M.Degree, V.Dergachev,
34 16 14 36 4 7 17 42
S.Desai, R.DeSalvo, S.Dhurandhar, M.Daz J.Dickson, A.Dietz, F.Donovan, K.L.Dooley,
31 5 17 54 16 10 16
E.E.Doomes, R.W.P.Drever, I.Duke, J.-C.Dumas, R.J.Dupuis, J.G.Dwyer, C.Echols,
18 16 8 16 16 19 7 54 16
A.Eer, P.Ehrens, G.Ely, E.Espinoza, T.Etzel, T.Evans, S.Fairhurst, Y.Fan, D.Fazi,
2 32 34 55 55 40 48 16,49
H.Fehrmann, M.M.Fejer, L.S.Finn, K.Flasch, N.Fotopoulos, A.Freise, R.Frey, T.Fricke,
17 19 19 18 1 19,20 49
P.Fritschel, V.V.Frolov, M.Fye, J.Garofoli, I.Gholami, J.A.Giaime, S.Giampanis,
19 17 46 16 20 2 20 43
K.D.Giardina, K.Goda, E.Goetz, L.Goggin, G.Gonzalez S.Gossler, R.Gouaty, A.Grant,
54 18 4 27 11 17 36
S.Gras, C.Gray, M.Gray, R.J.S.Greenhalgh, A.M.Gretarsson, F.Grimaldi, R.Grosso,
2 1 18 16 46 15 40
H.Grote, S.Grunewald, M.Guenther, E.K.Gustafson, R.Gustafson, B.Hage, J.M.Hallam,
55 20 19 2 17 48 36 27
D.Hammer, C.Hanna, J.Hanson, J.Harms, G.Harry, E.Harstad, K.Hayama, T.Hayler,
16 43 32 43 2 40 33 19
J.Heefner, I.S.Heng, M.Hennessy, A.Heptonstall, M.Hewitson, S.Hild, E.Hirose, D.Hoak,
39 43 43 18 48 16 18 20
D.Hosken, J.Hough, S.H.Huttner, D.Ingram, M.Ito, A.Ivanov, B.Johnson, W.W.Johnson,
52 7 43 54 10 26 10 44 40
D.I.Jones, G.Jones, R.Jones, L.Ju, P.Kalmus, V.Kalogera, S.Kamat, J.Kanner, D.Kasprzyk,
17 18 25 25 16 16 23
E.Katsavounidis, K.Kawabe, S.Kawamura, F.Kawazoe, W.Kells, D.G.Keppel, F.Ya.Khalili,
10 13 26 16 20 42 25 16
R.Khan, E.Khazanov, C.Kim, P.King, J.S.Kissel, S.Klimenko, K.Kokeyama, V.Kondrashov,
34 16 13 1 15 4 18
R.K.Kopparapu, D.Kozak, I.Kozhevatov, B.Krishnan, P.Kwee, P.K.Lam, M.Landry,
34 32 16 16 32 25 48 16
M.M.Lang, B.Lantz, A.Lazzarini, M.Lei, N.Leindecker, V.Leonhardt, I.Leonor, K.Libbrecht,
42 16 53 40 19 32 18 42
H.Lin, P.Lindquist, N.A.Lockerbie, D.Lodhia, M.Lormand, P.Lu, M.Lubinski, A.Lucianetti,
15,2 2 17 16 16 47 10
H.Luck B.Machenschalk, M.MacInnis, M.Mageswaran, K.Mailand, V.Mandic, S.Marka
10 32 17 16 43 42 16 17
Z.Marka A.Markosyan, J.Markowitz, E.Maros, I.Martin, R.M.Martin, J.N.Marx, K.Mason,
20 10 35 17 18 4 31
F.Matichard, L.Matone, R.Matzner, N.Mavalvala, R.McCarthy, D.E.McClelland, S.C.McGuire,
22 16 35 7 4 15 49
M.McHugh, G.McIntyre, G.McIvor, D.McKechan, K.McKenzie, T.Meier, A.Melissinos,
18 42 16 2 16 43,16 34 14
G.Mendell, R.A.Mercer, S.Meshkov, C.J.Messenger, D.Meyers, J.Miller, J.Minelli, S.Mitra,
23 42 17 16 55 36 18
V.P.Mitrofanov, G.Mitselmakher, R.Mittleman, O.Miyakawa, B.Moe, S.Mohanty, G.Moreno,
2 4 42 36 14 2 39
K.Mossavi, C.MowLowry, G.Mueller, S.Mukherjee, H.Mukhopadhyay, H.Muller-Ebhardt J.Munch,
43 18 18 16 43 43 25 24
P.Murray, E.Myers, J.Myers, T.Nash, J.Nelson, G.Newton, A.Nishizawa, K.Numata,
27 16 19 34 17 42 19
J.ODell G.Ogin, B.OReilly R.OShaughnessy D.J.Ottaway, R.S.Ottens, H.Overmier,
34 44 42 1,55 18 16 16
B.J.Owen, Y.Pan, C.Pankow, M.A.Papa, V.Parameshwaraiah, P.Patel, M.Pedraza,
12 40 34 51 43 2 43 50
S.Penn, A.Perreca, T.Petrie, I.M.Pinto, M.Pitkin, H.J.Pletsch, M.V.Plissi, F.Postiglione,
51 2 42 18 4 18 2 30
M.Principe, R.Prix, V.Quetschke, F.Raab, D.S.Rabeling, H.Radkins, N.Rainer, M.Rakhmanov,
34 2 43 42 19 46 18 16,43
M.Ramsunder, H.Rehbein, S.Reid, D.H.Reitze, R.Riesen, K.Riles, B.Rivera, N.A.Robertson,
7 40 19 20 56 10 36
C.Robinson, E.L.Robinson, S.Roddy, A.Rodriguez, A.M.Rogan, J.Rollins, J.D.Romano,
19 32 43 2 17 16 18 25 16
J.Romie, R.Route, S.Rowan, A.Rudiger L.Ruet, P.Russell, K.Ryan, S.Sakata, M.Samidi,
38 18 16 29 17 7
L.SanchodelaJordana, V.Sandberg, V.Sannibale, S.Saraf, P.Sarin, B.S.Sathyaprakash,
25 33 18 6 54 2 2 48
S.Sato, P.R.Saulson, R.Savage, P.Savov, S.W.Schediwy, R.Schilling, R.Schnabel, R.Schoeld,
1,7 18 4 4 16 2 19 16
B.F.Schutz, P.Schwinberg, S.M.Scott, A.C.Searle, B.Sears, F.Seifert, D.Sellers, A.S.Sengupta,
44 17 19 55 18 32 38,1
P.Shawhan, D.H.Shoemaker, A.Sibley, X.Siemens, D.Sigg, S.Sinha, A.M.Sintes,
4 20 33 16 17 2,1 43
B.J.J.Slagmolen, J.Slutsky, J.R.Smith, M.R.Smith, N.D.Smith, K.Somiya, B.Sorazu,
17 16 36 43 48 19 3
L.C.Stein, A.Stochino, R.Stone, K.A.Strain, D.M.Strom, A.Stuver, T.Z.Summerscales,
32 20 7 1 42 16 43 19
K.-X.Sun, M.Sung, P.J.Sutton, H.Takahashi, D.B.Tanner, R.Taylor, R.Taylor, J.Thacker,
34 6 15 43 19 43 19 38
K.A.Thorne, K.S.Thorne, A.Thuring K.V.Tokmakov, C.Torres, C.Torrie, G.Traylor, M.Trias,
16 37 32 32 15 7 26
Tyler, D.Ugolini, J.Ulmen, K.Urbanek, H.Vahlbruch, C.VanDenBroeck, M.vanderSluys,
16 55 40 40 39 8 16 18
S.Vass, R.Vaulin, A.Vecchio, J.Veitch, P.Veitch, S.Vigeland, A.Villar, C.Vorvick,
23 16 16 43 16 2 16 17
Vyachanin, S.J.Waldman, L.Wallace, H.Ward, R.Ward, M.Weinert, A.Weinstein, R.Weiss,
20 4 1 34 16 42 18
Wen, K.Wette, J.T.Whelan, D.M.Whitbeck, S.E.Whitcomb, B.F.Whiting, C.Wilkinson,
16 34 42 15,2 27 2 17
.A.Willems, H.R.Williams, L.Williams, B.Willke, I.Wilmut, W.Winkler, C.C.Wipf,
55 43 19 18 42 19 16 54
G.Wiseman, G.Woan, R.Wooley, J.Worden, W.Wu, I.Yakushin, H.Yamamoto, Z.Yan,
30 11 46 16 54 21 17 16
.Yoshida, M.Zanolin, J.Zhang, L.Zhang, C.Zhao, N.Zotov, M.Zucker, andJ.Zweizig
(TheLIGOScienticCollaboration,http://www.ligo.org)
1
Albert-Einstein-Institut,Max-Planck-InstitutfurGravitationsphysik,D-14476Golm,German
2
Albert-Einstein-Institut,Max-Planck-InstitutfurGravitationsphysik,D-30167Hannover,German
3
AndrewsUniversity,BerrienSprings,MI49104USA
4
AustralianNationalUniversity,Canberra,0200,Australia
5
CaliforniaInstituteofTechnology,Pasadena,CA91125,USA
6
Caltech-CaRT,Pasadena,CA91125,USA
7
CardiUniversity,Cardi,CF243AA,UnitedKingdom
8
CarletonCollege,Northeld,MN55057,USA
9
CharlesSturtUniversity,WaggaWagga,NSW2678,Australia
10
ColumbiaUniversity,NewYork,NY10027,USA
11
Embry-RiddleAeronauticalUniversity,Prescott,AZ86301USA
12
HobartandWilliamSmithColleges,Geneva,NY14456,USA
13
InstituteofAppliedPhysics,NizhnyNovgorod,603950,Russia
14
Inter-UniversityCentreforAstronomyandAstrophysics,Pune-411007,India
15
LeibnizUniversitatHannover,D-30167Hannover,German
16
LIGO-CaliforniaInstituteofTechnology,Pasadena,CA91125,USA
17
LIGO-MassachusettsInstituteofTechnology,Cambridge,MA02139,USA
18
LIGOHanfordObservatory,Richland,WA99352,USA
19
LIGOLivingstonObservatory,Livingston,LA70754,USA
20
LouisianaStateUniversity,BatonRouge,LA70803,USA
21
LouisianaTechUniversity,Ruston,LA71272,USA
22
LoyolaUniversity,NewOrleans,LA70118,USA
23
MoscowStateUniversity,Moscow,119992,Russia
24
NASA/GoddardSpaceFlightCenter,Greenbelt,MD20771,USA
25
NationalAstronomicalObservatoryofJapan,Tokyo181-8588,Japan
26
NorthwesternUniversity,Evanston,IL60208,USA
27
RutherfordAppletonLaboratory,Chilton,Didcot,OxonOX110QXUnitedKingdom
28
SanJoseStateUniversity,SanJose,CA95192,USA
29
SonomaStateUniversity,RohnertPark,CA94928,USA
30
SoutheasternLouisianaUniversity,Hammond,LA70402,USA
31
SouthernUniversityandA&MCollege,BatonRouge,LA70813,USA
32
StanfordUniversity,Stanford,CA94305,USA
33
SyracuseUniversity,Syracuse,NY13244,USA
34
ThePennsylvaniaStateUniversity,UniversityPark,PA16802,USA
35
TheUniversityofTexasatAustin,Austin,TX78712,USA
36
TheUniversityofTexasatBrownsvilleandTexasSouthmostCollege,Brownsville,TX78520,USA
37
TrinityUniversity,SanAntonio,TX78212,USA
38
UniversitatdelesIllesBalears,E-07122PalmadeMallorca,Spain
39
UniversityofAdelaide,Adelaide,SA5005,Australia
40
UniversityofBirmingham,Birmingham,B152TT,UnitedKingdom
41
UniversityofCaliforniaatBerkeley,Berkeley,CA94720USA
42
UniversityofFlorida,Gainesville,FL32611,USA
43
UniversityofGlasgow,Glasgow,G128QQ,UnitedKingdom
44
UniversityofMaryland,CollegePark,MD20742USA
45
UniversityofMassachusetts,Amherst,MA01003USA
46
UniversityofMichigan,AnnArbor,MI48109,USA
47
UniversityofMinnesota,Minneapolis,MN55455,USA
48
UniversityofOregon,Eugene,OR97403,USA
49
UniversityofRochester,Rochester,NY14627,USA
50
UniversityofSalerno,84084Fisciano(Salerno),Italy
51
UniversityofSannioatBenevento,I-82100Benevento,Italy
52
UniversityofSouthampton,Southampton,SO171BJ,UnitedKingdom
53
UniversityofStrathclyde,Glasgow,G11XQ,UnitedKingdom
54
UniversityofWesternAustralia,Crawley,WA6009,Australia
2
55
UniversityofWisconsin-Milwaukee,Milwaukee,WI53201,USA
56
WashingtonStateUniversity,Pullman,WA99164,USA
(Dated:April10,2008)
Asearchforperiodicgravitationalwaves,fromsourcessuchasisolatedrapidly-spinningneutron
stars,wascarriedoutusing510hoursofdatafromthefourthLIGOsciencerun(S4).Thesearch
wasforquasi-monochromaticwavesinthefrequencyrangefrom50Hzto1500Hz,withalinear
frequencydrift f (measuredatthesolarsystembarycenter)intherangef f< 01f,
wheretheminimumspin-downage was1000yearsforsignalsbelow300Hzand10000yearsabove
300Hz.Themaincomputationalworkofthesearchwasdistributedoverapproximately100000
computersvolunteeredbythegeneralpublic.Thislargecomputingpowerallowedtheuseofa
relativelylongcoherentintegrationtimeof30hours,despitethelargeparameterspacesearched.
Nostatisticallysignicantsignalswerefound.Thesensitivityofthesearchisestimated,alongwith
thefractionofparameterspacethatwasvetoedbecauseofcontaminationbyinstrumentalartifacts.
Inthe100Hzto200Hzband,morethan90%ofsourceswithdimensionlessgravitationalwavestrain23
amplitudegreaterthan10 wouldhavebeendetected.
PACSnumbers:04.80.Nn,95.55.Ym,97.60.Gb,07.05.Kf
I.INTRODUCTION stars[8,9,10,11,12,13,14,15,16].
IftherewerenoaccelerationbetweentheLIGOde-
tectorsandtheGWsources,thenitwouldbepossible
Gravitationalwavesareafundamentalpredictionof
tosearchforCWsignalsfromunknownsourcesusing
EinsteinsGeneralTheoryofRelativity[1,2].Butthes
onlystandardcomputingresources,suchasahig
wavesareveryweak,soalthoughthereiscompellingin-
endworkstationorasmallcomputingcluster.Inthis
directevidencefortheirexistence[3],directdetectionhas
casetheanalysistechniquewouldbesimple:compute
sofarnotbeenpossible.
theFastFourierTransform(FFT)[17,18]oftheoriginal
Inthepastdecade,advancesinlasers,opticsandcon-
time-seriesdata,andsearchalongthefrequencyaxisfor
trolsystemshaveenabledconstructionofanewgener-
peaksinthepowerspectrum.Time-domainresampling
ationofgravitational-wavedetectors[4]thatoerthe
orsimilartechniquescouldbeusedtocompensateforthe
rstrealisticpromiseofadirectdetection.TheLaser
eectsofalinear-in-timefrequencydrift.
InterferometerGravitational-waveObservatory(LIGO)
[5,6]iscurrentlythemostsensitiveoftheseinstruments.
However,thissimpleanalysisisnotpossiblebecause
LIGOconsistsofthreekilometer-scaleinstruments.Two
oftheterrestriallocationoftheLIGOdetectors:sig-
arelocatedinacommonvacuumenvelopeinHanford,
nalsthatarepurelysinusoidalatthesourceareDoppler-
Washington,USAandtheotherislocatedinLivingston,
modulatedbytheEarthsmotionandthusarenolonge
Louisiana,USA.
sinusoidalatthedetector.TheEarthsrotationabou
ThispaperreportsontheresultsoftheEin-
itsaxismodulatesthesignalfrequencyatthedetector
6
[email=stein@Homesearchforcontinuouswavesourcesint]stein@Homesearchforcontinuouswavesourcesint[/email]
byapproximatelyonepartin10 ,withaperiodofone
datafromthefourthLIGOsciencerun(S4).Thecon-
siderealday.Inaddition,theEarthsorbitaboutth
gurationoftheLIGOdetectorsduringtheS4runis
Sunmodulatesthesignalfrequencyatthedetectorby
4
describedinaseparateinstrumentalpaper[7].
approximatelyonepartin10 ,withaperiodofoneyear.
Thesetwomodulations,whoseexactformdependsupon
thepreciseskylocationofthesource,greatlycomplicate
thedataanalysiswhensearchingforunknownsources.
A.Continuouswave(CW)sourcesanddetection
methods
ThesearchbecomesevenmorecomplicatediftheCW-
emitterispartofabinarystarsystem,sincetheorbital
motionofthebinarysystemintroducesadditionalmod-
Continuouswaves(CW)arequasi-monochromat
ulationsintothewaveform.
gravitational-wavesignalswhosedurationislongerthan
theobservationtime.Theyhaveawell-denedfrequency Thebruteforceapproachtothedataanalysispro
onshorttime-scales,whichcanvaryslowlyoverlonger lemwouldemploymatchedltering,convolvingallavail-
times.Thesetypesofwavesareexpected,forexample, abledatawithafamilyoftemplatewaveformscorre-
fromspinningneutronstarswithnon-axisymmetricde- spondingtoallpossibleputativesources.Theresulting
formations.Ifthesystemisisolated,thenitlosesangular searchstatisticiscalledthe F-statisticandwasrstde-
momentumtotheradiation.Thespinningslowsdown, scribedinaseminalpaperofJaranowski,Krolak,an
andthegravitational-wavefrequencydecreases.Gravi- Schutz[19].Butevenforisolatedneutronstars(i.e.
tationalaccelerationtowardsalargenearbymassdistri- whicharenotinbinarysystems)theparameterspace
butioncanalsoproducesuchafrequencydrift(ofeither ofpossiblesourcesisfour-dimensional,withtwoparam-
etersrequiredtodescribethesourceskypositionusing
sign).Manypossibleemissionmechanismscouldlead
standardastronomicalequatorialcoordinates (rightas-
thetotheemissionofsuchwavesbyspinningneutron
3
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发表于 2008-8-17 22:21:30
发表于 2008-8-18 10:56:44
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