THE SOLAR NEIGHBORHOOD. XV. DISCOVERY OF NEW HIGH PROPER MOTION STARS WITH 0B4 yr 1 BETWEEN DECLINATIONS 47 AND 00

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1 The Astronomicl Journl, 130: , 2005 October # The Americn Astronomicl Society. All rights reserved. Printed in U.S.A. A THE SOLAR NEIGHBORHOOD. XV. DISCOVERY OF NEW HIGH PROPER MOTION STARS WITH 0B4 yr 1 BETWEEN DECLINATIONS 47 AND 00 John P. Subsvge nd Todd J. Henry Deprtment of Physics nd Astronomy, Georgi Stte University, 1 Prk Plce, Suite 700, Atlnt, GA ; subsvge@chr.gsu.edu, thenry@chr.gsu.edu Nigel C. Hmbly Institute for Astronomy, University of Edinburgh Royl Observtory, Blckford Hill, Edinburgh EH9 3HJ, Scotlnd, UK; nch@roe.c.uk nd Misty A. Brown, Wei-Chun Jo, nd Chrlie T. Finch Deprtment of Physics nd Astronomy, Georgi Stte University, 1 Prk Plce, Suite 700, Atlnt, GA ; brown@chr.gsu.edu, jo@chr.gsu.edu, finch@chr.gsu.edu Received 2005 April 22; ccepted 2005 June 29 ABSTRACT We report the discovery of 152 new high proper motion systems ( 0B4yr 1 ) in the southern sky ( ¼ 47 to 00 ) brighter thn UKST plte R 59F ¼ 16:5 vi our SuperCOSMOS-RECONS (SCR) serch. This pper complements Pper XII in the Solr Neighborhood series, which covered the region from ¼ 90 to 47 nd discussed ll 147 new systems from the southernmost phse of the serch. Among the totl of 299 systems from both ppers, there re 148 (71 in Pper XII, 77 in this pper) new systems moving fster thn 0B5yr 1 tht re dditions to the clssic Luyten Hlf Second smple. These constitute n 8% increse in the smple of ll stellr systems with 0B5yr 1 in the southern sky. As in Pper XII, distnce estimtes re provided for the systems reported here bsed on combintion of photogrphic plte mgnitudes nd Two Micron All Sky Survey photometry, ssuming tht ll strs re on the min sequence. Two SCR systems from the portion of the sky included in this pper re nticipted to be within 10 pc, nd n dditionl 23 re within 25 pc. In totl, the results presented in Pper XII nd here for this SCR sweep of the entire southern sky include five new systems within 10 pc nd 38 more between 10 nd 25 pc. The lrgest number of nerby systems hve been found in the slowest proper motion bin, 0B6 yr 1 > 0B4 yr 1, indicting tht there my be lrge popultion of low proper motion systems very ner the Sun. Key words: solr neighborhood strs: distnces strs: sttistics Online mteril: mchine-redble tble 1. INTRODUCTION In this pper we continue our reconnissnce of the solr neighborhood by reporting results of the second phse of our SuperCOSMOS-RECONS (SCR) serch for new high proper motion (HPM) objects in the southern sky. In Pper XII of the Solr Neighborhood (TSN) series (Subsvge et l. 2005), we presented results for the portion of the sky between declintions 90 nd 47. In this pper we cover the region from declintions 47 to 00. Recently, the northern sky hs been serched systemticlly for HPM objects by Lépine et l. (2002, 2003) utilizing SUPERBLINK, which hs been prticulrly successful t filling in the distribution of HPM objects long the Glctic plne. Their ltest compendium (Lépine & Shr 2005) includes 61,977 HPM objects with 0B15 yr 1. The totl number of objects is roughly double wht ws found during the pioneering dys of Gicls et l. (1971, 1978) nd Luyten (1979, ). Historiclly, however, the southern sky hs been investigted with limited depth for HPM objects, which re notoriously good nerby str cndidtes. Since the Gicls et l. nd Luyten efforts, significnt numbers of HPM strs hve been found, primrily becuse of the dvent 1 Informtion is vilble from the VizieR Online Dt Ctlog, ctlog number of lrge dtbses holding dt from digitized photogrphic pltes. Some of the new discoveries re remrkbly nerby, including SO (Teegrden et l. 2003), DENIS (Delfosse et l. 2001), nd SCR (Hmbly et l. 2004, herefter Pper VIII), which hve distnces estimted to be 3.7, 4.5, nd 4.6 pc, respectively (Henry et l. 2004, herefter Pper X). Becuse of their proximity, these three red dwrfs re high-priority trgets in our trigonometric prllx progrm, CTIOPI (Cerro Tololo Inter-Americn Observtory Prllx Investigtion) being crried out in Chile (Jo et l. 2005; Henry et l. 2005). As is the cse for ll of the recent HPM surveys, the new SCR discoveries re primrily red dwrfs tht re underrepresented in current compendi of solr neighborhood membership lists becuse of their intrinsic fintness (Henry et l.1997). Additionl smtterings of white dwrfs nd subdwrfs re lso found in the SCR nd other HPM serches. The clssic work of Gicls et l. nd Luyten hs been complemented by the recent HPM surveys summrized in Tble 1, ech of which hs reveled importnt new HPM objects. (The mchine-selected ctlog of 11,289 objects generted by Pokorny et l. [2004] remins difficult to ssess, becuse our initil checks indicte tht mny of the objects re previously known nd severl re not rel HPM sources.) We compre the number of new discoveries from ech survey to the Luyten Hlf Second ( LHS) Ctlogue ( Luyten 1979), which included 3602 objects with proper motions in excess of 0B5 yr 1 nd still ccounts for

2 THE SOLAR NEIGHBORHOOD. XV TABLE 1 Proper-Motion Surveys nd Number of New LHS Objects Discovered Survey 1B0 yr 1 1B0 yr 1 > 0B5 yr 1 Totl Number of Publictions References LHS SUPERBLINK SuperCOSMOS-RECONS , 4, 5, 6 SIPS (Decon et l.) WT (Wroblewski nd collbortors) , 9 Scholz nd collbortors Cln-ESO (Ruiz nd collbortors) , 12 Oppenheimer et l Pokorny et l... Unknown Unknown Unknown 2 14 References. (1) Luyten 1979; (2) Lépine et l. 2002, 2003; (3) Pper VIII; (4) Pper X; (5) Pper XII; (6) this pper; (7) Decon et l. 2005b; (8) Wroblewski & Torres 1989, 1991, 1994, 1996, 1997; (9) Wroblewski & Cost 1999, 2001; (10) Scholz et l. 2000, 2002, 2004, 2004b; (11) Ruiz & Mz 1987; (12) Ruiz et l. 2001; (13) Oppenheimer et l. 2001; (14) Pokorny et l. 2003, % of ll known such objects. This revels the enormous impct of the work by Gicls et l. nd Luyten, who crried out their surveys in times before mssive computer serches of digitized photogrphic pltes were possible. 2. SEARCH METHODOLOGY To revel new HPM objects, we mine the SuperCOSMOS dtbse developed nd mintined t the Royl Observtory in Edinburgh, Scotlnd. Ppers VIII, X, nd XII in this series include previous discoveries from our SCR survey. The serch techniques used here re identicl to those in Pper VIII, in which full discussion cn be found. Briefly, we use the SuperCOSMOS Sky Survey to revel previously unknown HPM objects using combintion of strometric nd photometric informtion from the four photogrphic pltes vilble (B J,ESO R, R 59F,ndI IVN )inthe southern sky. In Pper XII, 1424 cndidte objects were found hving 10B0 yr 1 >0B4 yr 1 nd re brighter thn R 59F ¼ 16:5. In this portion of the serch, we hve found n dditionl 3879 cndidtes meeting the sme criteri. The combined coverge of the two portions of the survey includes 46% of the entire sky nd 92% of the southern sky, where we hve serched from the south celestil pole t ¼ 90 to northern cutoff t precisely ¼ 00 (even though the pltes typiclly extend to ¼ 3N0). Figure 1 is mp of the sky coverge, including the 894 plte fields in the southern sky. Seventy-one fields hve not been serched becuse of crowding ner the Glctic plne nd Mgellnic Clouds or becuse of limited spred in epochs for vilble pltes. The vetting of cndidtes, which includes checks of proper motions, mgnitudes, colors, nd imge ellipticities, s well s inspection by eye, ws described in detil in Pper XII. For ech cndidte tht ppered to be rel object, coordintes were crefully cross-checked with the New Luyten Two-Tenths (NLTT) Ctlogue, the SIMBAD dtbse, nd recent HPM publictions (see Tble 1) to see whether it ws known object. If the coordintes greed to within few rcminutes nd the mgnitudes nd proper motions were consistent, the detection ws considered previously known. In few cses, the coordintes nd proper motions greed well but the mgnitudes did not. These objects were reveled to be new wide common proper motion compnions to previously known proper motion strs; four new compnions re reported here (see x 5.5). Overll, the hit rte for new HPM objects decreses with incresing proper motion, becuse relible source ssocition between different epochs is more difficult for fstmoving sources. For objects with 10B0 yr 1 > 1B0 yr 1, only 10% turn out to be rel, wheres 87% of objects detected with 1B0 yr 1 > 0B4 yr 1 re rel. These frctions include both new nd known objects. The finl count of rel, distinct, new systems with 10B0 yr 1 > 0B4 yr 1 nd brighter thn R 59F ¼ 16:5 found between ¼ 47 nd 00 is 152. We continue using our nming convention, SCR, for objects discovered during the survey. 3. COMPARISON TO PREVIOUS PROPER-MOTION SURVEYS A primry gol of the SCR effort is to further complete the LHS Ctlogue for strs with 0B5yr 1. Our extension of the cutoff to 0B4 yr 1 in this survey is to ensure tht no known LHS strs were missed due to proper-motion mesurement errors for objects very ner the 0B5 yr 1 limit. Of the 299 new SCR systems found to dte, 148 hve 0B5yr 1. Figure 2 provides mp of new systems with 0B5yr 1, including the 148 totl SCR systems ( filled tringles representing 150 individul objects) tht re dditions to the LHS smple. Lépine et l. (2002, 2003) nd Lépine & Shr (2005) hve completed work on the entire northern sky using SUPERBLINK nd re so fr the most productive survey for reveling new objects with 0B5yr 1. Although we void the Glctic plne nd Mgellnic Clouds, the SCR survey hs the most uniform sky coverge for southern hemisphere serches nd is consequently the most productive survey in the southern hemisphere. There re undoubtedly objects remining to be discovered long the crowded Glctic plne in the southern sky; the gps in Figure 2 typiclly mtch the regions not serched (white spces in Fig. 1). The sme is true of the LMC ( ¼ 05 h 30 m, ¼ 68 ) nd SMC ( ¼ 01 h 00 m, ¼ 73 ) regions. There re 1462 LHS strs in the LHS Ctlogue brighter thn photogrphic R mgnitude (R pg ) of 16.5 in the southern sky. Of the 1152 known LHS strs in the southern sky with 10:0 < R pg < 16:5, we hve recovered 1032 (90%). We recover only 234 of 310 (75%) LHS strs brighter thn R ¼ 10:0, becuse the serch is somewht less sensitive to bright objects tht re sturted in the photogrphic emulsions. This recovery rte is somewht less successful for strs moving fster thn 1B0 yr 1 (199 of 251, 79%) thn for strs with ¼ 0B5 1B0yr 1 (1067 of 1211, 88%). 4. DATA As in Pper XII, coordintes, proper motions, nd plte mgnitudes hve been extrcted from SuperCOSMOS for the new HPM systems. These dt re listed in Tble 2 for objects in the

3 Fig. 1. Plte coverge of the entire SCR survey, including sky coverge in Pper XII nd this pper. Pltes colored in white were excluded from the serch, primrily becuse of source crowding (Glctic plne, LMC, nd SMC) or limited time spn between pltes.

4 THE SOLAR NEIGHBORHOOD. XV Fig. 2. Sky distribution of new LHS objects from recent proper-motion surveys. Only strs with 0B5 yr 1 re plotted. Filled tringles re from the SCR survey discussed here nd in Pper XII. Crosses represent objects from the SUPERBLINK survey. Other symbols represent objects from other surveys: WT (open circles), Scholz (open tringles), Cln-ESO (open squres), Oppenheimer (open strs), nd SIPS (open dimonds). The curve represents the Glctic plne, where more high proper motion objects re yet to be reveled. new portion of the sky serched here. Coordintes re for epoch nd equinox J Errors in the coordintes re typiclly 0B3, nd errors in the proper motions re given. Errors in position ngle re usully 0N1. Photometric mgnitudes re given for three sets of pltes: B J, R 59F, nd I IVN. Mgnitude errors re 0.3 mg or better for m > 15 nd ctully get lrger t brighter mgnitudes due to systemtic errors (Hmbly et l. 2001). A few plte mgnitude vlues re missing becuse of blending problems tht preclude ccurte mgnitude determintions. Infrred photometry hs been used to extend the color bseline, which llows more ccurte photometric distnce estimtes for red dwrfs nd permits relible seprtion of the white nd red dwrfs. The infrred JHK s photometry hs been extrcted from the Two Micron All Sky Survey (2MASS) vi Aldin. Ech SCR object hs been identified by eye to ensure tht no extrcted mgnitudes re in error. In nerly every cse, the errors re smller thn 0.03 mg. Exceptions include objects with J > 15, H > 14:5, nd K s > 14, for which the errors re 0.05 mg or greter. In one cse, SCR , the error is null for K s, nd the vlue is therefore unrelible. 5. ANALYSIS 5.1. Color-Mgnitude Digrm Illustrted in Figure 3 is color pprent mgnitude digrm tht compres new SCR objects (split into lrge filled circles representing objects with 0B5 yr 1 nd smll filled circles representing objects with 0B5 yr 1 > 0B4 yr 1 ) to previously known strs hving 0B5 yr 1. As in Pper XII, the SCR discoveries re generlly finter nd redder thn the bulk of the known strs (note tht the open/filled symbols hve been exchnged reltive to Pper XII for clrity in this figure). However, the portion of sky serched in this pper is much lrger (2.2 times the re) thn tht trgeted in Pper XII nd overlps the regions serched by Gicls et l. (1971, 1978) nd Luyten (1979, 1980). This results in two importnt differences from the similr Figure 4 in Pper XII. First, there re fr more known objects shown here thn in the deep southern sky. Second, becuse Luyten s Bruce Proper Motion survey for the sky south of Fig. 3. Color pprent mgnitude digrm for the SCR systems with 0B4yr 1 (the size of the points splits the SCR smple into strs with more or less thn 0B5yr 1 ) nd known systems with 0B5yr 1 found in this portion of the SCR survey from declintions 47 to 00. Tringles indicte confirmed white dwrfs. ¼ 33 hd reltively bright limit (m pg 15:5) nd lcked red pltes, there were very few known fint strs in the complementry figure of Pper XII. Here there re mny fint strs from the overlp region between ¼ 33 nd 00 where erlier serches did hve fint limits. Note lso tht there re 43 white dwrfs here (39 known nd 4 new cndidtes), wheres there were 16 in Pper XII, entirely consistent with uniform white dwrf distribution on the sky given the rtio of sky res serched. We hve not found ny dditionl extremely red objects similr to SCR (R 59F J ¼ 7:79, R 59F ¼ 16:33, Pper VIII; V K s ¼ 8:89, M8.5V, distnce estimte 4.6 pc, Pper X; trigonometric prllx ms, Decon et l. 2005) in this portion of the sky. Insted, the remrkble find is SCR with R 59F J ¼ 1:95, R 59F ¼ 8:79, nd distnce estimted here to be 8.5 pc, ssuming it is single (see x 5.5). Tht such bright object remined unidentified until this survey is surprising, indicting yet gin tht there my be very nerby, reltively bright strs tht hve not yet been found. As noted in Pper XII, there is not significnt drop in the number of objects t our dopted fint limit, so there is likely to remin lrge popultion of finter objects yet to be discovered in the SuperCOSMOS dt. Moreover, the popultion of objects with <0B5yr 1 hs brely been investigted, lthough portion of the previously known objects in the NLTT hve been exmined (Reid et l. 2004) Reduced Proper Motion Digrm Shown in Figure 4 is the reduced proper motion (RPM) digrm for objects from the region of the sky reported here. The RPM digrm is used to seprte effectively the white dwrfs from min-sequence strs, s well s to ssist in identifying subdwrfs. The ssumption is, of course, tht proper motion is directly relted to distnce. A complementry plot cn be found in Figure 5 of Pper XII for the southernmost portion of the SCR survey. As in Pper XII it is pprent tht most of the new SCR strs re min-sequence red dwrfs, while there is substntil smple of new subdwrf cndidtes; note the bifurcted popultion of circles running from the upper left to lower right in Figure 4. The re just bove the dotted line mps out the subdwrf region. The dotted

5 TABLE 2 Proper Motions, Photogrphic nd Infrred Photometry, nd Distnce Estimtes for the SuperCOSMOS-RECONS Smple with 0B4 yr 1 from 47 > >00 Nme R.A. (J2000.0) Decl. (J2000.0) (rcsec) (rcsec) (deg) B J R 59F I IVN J H K s R 59F J Est. Distnce ( pc) Notes SuperCOSMOS-RECONS Smple with 0B5 yr SCR [515.7] SCR SCR SCR SCR SCR SCR [104.9] SCR [234.3] SCR SCR SCR SCR SCR SCR SCR SCR SCR SCR SCR SCR SCR SCR [200.4] SCR SCR SCR SCR SCR SCR SCR [95.4] SCR SCR SCR SCR [99.4] SCR SCR SCR SCR SCR [150.8] SCR [188.2] SCR SCR SCR SCR SCR [199.7] SCR ,b b, c c

6 TABLE 2 Continued Nme R.A. (J2000.0) Decl. (J2000.0) (rcsec) (rcsec) (deg) B J R 59F I IVN J H K s R 59F J Est. Distnce (pc) Notes 1663 SCR SCR [130.8] SCR [215.1] SCR SCR SCR SCR SCR SCR AB SCR [143.0] SCR SCR SCR SCR SCR SCR SCR SCR SCR SCR [138.9] SCR [199.2] SCR SCR [149.8] SCR SCR SCR SCR SCR SCR SCR SCR [120.6] SCR d e SuperCOSMOS-RECONS Smple with between 0B4 nd 0B5 yr 1 SCR [124.6] SCR SCR SCR [93.7] SCR SCR [131.3] SCR SCR SCR SCR SCR SCR [166.4] SCR

7 TABLE 2 Continued Nme R.A. (J2000.0) Decl. (J2000.0) (rcsec) (rcsec) (deg) B J R 59F I IVN J H K s R 59F J Est. Distnce ( pc) Notes 1664 SCR SCR [365.2] SCR [224.3] SCR SCR SCR [195.0] SCR SCR SCR SCR SCR [119.5] SCR SCR SCR [328.5] SCR SCR SCR SCR SCR SCR SCR SCR SCR SCR [166.2] SCR SCR SCR SCR SCR [141.6] SCR [295.4] SCR SCR SCR [215.6] SCR SCR SCR SCR SCR SCR SCR SCR [125.4] SCR SCR [147.6] SCR [197.3] SCR SCR SCR SCR ,b,f c, g h i

8 TABLE 2 Continued Nme R.A. (J2000.0) Decl. (J2000.0) (rcsec) (rcsec) (deg) B J R 59F I IVN J H K s R 59F J Est. Distnce (pc) Notes 1665 SCR SCR A SCR B SCR SCR [228.7] SCR [121.6] SCR SCR SCR SCR SCR SCR SCR SCR SCR SCR SCR SCR SCR j e k Notes. Units of right scension re hours, minutes, nd seconds, nd units of declintion re degrees, rcminutes, nd rcseconds. Tble 2 is lso vilble in mchine-redble form in the electronic edition of the Astronomicl Journl. Distnce is likely overestimted becuse the object is subdwrf or white dwrf cndidte (see x 5.3). b Probble white dwrf. c All colors re too blue for distnce reltions. d Seprtion of 2B5 t position ngle 266N2. e No distnce estimte is reported becuse only one color ws vilble within the bounds of the reltions. f Common proper motion with LTT g White dwrf ; K s unrelible. h Common proper motion with CD i Common proper motion with L j Not detected during utomted serch due to fint limit but noticed to be common proper motion compnion during the visul inspection, blended on ll four pltes. k Common proper motion with LTT 8495.

9 1666 SUBASAVAGE ET AL. Vol. 130 TABLE 3 Red Subdwrf Cndidtes from Pper XII nd This Pper Nme R 59F R 59F J H R TSN Pper Fig. 4. Reduced proper motion digrm for the SCR systems with 0B4yr 1 (the size of the points splits the SCR smple into strs with more or less thn 0B5yr 1 ) nd known systems with 0B5 yr 1 foundinthisportionofthe SCR survey from declintions 47 to 00. Reduced proper motion (verticl xis) hs units of mgnitudes. The dshed line serves merely s reference to distinguish white dwrfs from subdwrfs. Tringles indicte confirmed white dwrfs. line represents somewht rbitrry boundry between the subdwrfs nd white dwrfs. There re four cler white dwrf cndidtes, two of which re confirmed white dwrfs ( filled tringles) for one we hve confirmtion spectrum, nd the other is common proper motion compnion to str of known distnce Red Dwrfs nd Subdwrfs The combintion of the B J, R 59F, nd I IVN plte mgnitudes nd JHK s photometry from 2MASS llows us to estimte distnces to min-sequence strs, s described in Pper VIII. The six mgnitudes provide 15 color-m Ks combintions, 11 of which cn be used to estimte individul distnces (JHK s -only colors re not used becuse of limited color discrimintion, nd B J R 59F is not sensitive to bsolute mgnitude for cooler dwrfs). The reltions ssume tht the objects re single, min-sequence dwrfs of types K0 V to M9 V. The distnces hve n verge error of 26%, determined by running the RECONS 10 pc smple of single red dwrfs with known distnces through the suite of photometric distnce reltions. For our investigtion, the most interesting strs re those tht re potentilly nerby, specificlly within the volumes defined by the RECONS 10 pc nd the Ctlog of Nerby Strs (Gliese & Jhreiss 1991) nd Nerby Strs (NStrs) smples (horizons t 25 pc). Distnce estimtes for the 152 new systems in the portion of the sky serched here re given in the next-to-lst column of Tble 2. If only one color ws vilble for distnce estimte, no distnce is reported, becuse the single color flling within the bounds of the reltions is possibly berrnt. Two of the systems, SCR nd SCR , re new cndidtes for the 10 pc smple, nd n dditionl 23 systems re estimted to be between 10 nd 25 pc. There re nine SCR strs hving distnce estimtes in excess of 200 pc (excluding white dwrf cndidtes) nd severl more with distnce estimtes very close to 200 pc, most of which fll bluewrd of the mjority of SCR strs in Figure 4. These re presumbly K- nd M-type subdwrfs. A smple of 64 potentil SCR red subdwrfs from Pper XII nd this pper is listed in its entirety in Tble 3. These hve been selected by identifying strs in Figure 4 (nd the twin figure in Pper XII) with R 59F J > 1:0 nd hving RPM H R within 4.0 mg of the dshed line SCR XII SCR XII SCR XII SCR XII SCR XV SCR XII SCR XII SCR XV SCR XV SCR XV SCR XV SCR XV SCR XV SCR XV SCR XII SCR XV SCR XV SCR XV SCR XV SCR XV SCR XV SCR XV SCR XV SCR XII SCR XII SCR XV SCR XV SCR XV SCR XII SCR XV SCR XV SCR XV SCR XV SCR XV SCR XV SCR XV SCR XII SCR XII SCR XII SCR XII SCR XII SCR XII SCR XV SCR XV SCR XII SCR XII SCR XV SCR XV SCR XV SCR XII SCR XII SCR XII SCR XII SCR XII SCR XII SCR XII SCR XII SCR XV SCR XII SCR XII SCR XII SCR XII SCR XII SCR XII

10 No. 4, 2005 THE SOLAR NEIGHBORHOOD. XV seprting the white dwrfs from the subdwrfs. All of these hve distnces estimted to be 90 pc or greter, but they re, in fct, likely to be much closer thn estimted (i.e., the distnces re incorrect), so their distnce estimtes re brcketed in Tble 2 to distinguish them from presumed dwrfs whose distnce estimtes re plusibly ccurte. In the sme regions in Figure 4 nd the complimentry figure in Pper XII, there re 255 red subdwrf cndidtes from previous proper-motion serches. Thus, we hve mde 25% increse to the red subdwrf cndidte pool in the southern sky. Future spectroscopic efforts will revel whether or not these cndidtes re true low-metllicity red subdwrfs nd will llow us to continue building sizeble smple of these rre interlopers to the solr neighborhood, very few of which hve ccurte prllxes, photometry, nd spectrl types White Dwrfs Six of the SCR strs reported here hve no distnce estimtes, usully becuse their colors re too blue for the photometric distnce reltions. SCR , SCR , nd SCR re possibly erly-type subdwrfs, nd SCR B is compnion with blended plte photometry (see x 5.5). The remining two strs, SCR nd SCR , re white dwrf cndidtes. Both lie solidly in the white dwrf region of Figure 4. Two dditionl SCR strs, SCR nd SCR ( compnion to LTT 2976), lso fll clerly in the white dwrf region of Figure 4 nd hve the lrgest distnce estimtes presented here (516 nd 365 pc, respectively). These objects hve colors tht re within the color rnges of the photometric distnce reltions but re presumbly white dwrfs with erroneous distnce estimtes, hence the brckets in Tble 2. Two dditionl objects, SCR nd SCR , re ner the dotted line dividing the probble white dwrf nd subdwrf regions. We hve preliminry CCD VRI photometry indicting tht these two objects re unlikely to be single white dwrfs. Of the four white dwrf cndidtes, we hve so fr obtined spectroscopy on only SCR nd confirm it to be white dwrf. Another cndidte (SCR ) is compnion to str of known distnce (thereby ruling it out s more distnt erly-type dwrf ). Spectroscopic observtions for ll white dwrf cndidtes re desired for definitive confirmtion. Spectr for SCR s well s for hndful of the objects lbeled with open tringles in Figure 4 s known objects tht we hve confirmed to be white dwrfs for the first time will be presented in future publiction. Using the single-color liner fit of Oppenheimer et l. (2001) nd their error of 20% for distnces, we estimte the following distnces for the four white dwrf cndidtes reported in this pper: 24:7 4:9 pc for SCR , 16:2 3:2 pc for SCR , 13:1 2:6 pc for SCR , nd 40:0 8:0 pc for SCR Should these distnce estimtes hold true, three of the four objects lie within the 25 pc horizon, volume in which there re only 109 white dwrfs currently hving trigonometric prllxes. Trigonometric prllx observtions vi CTIOPI re under wy to determine ccurte distnces Comments on Individul Systems Here we highlight systems included in this portion of the SCR survey, most of which re multiple systems. SCR ( ¼ 0B592 yr 1 t position ngle 170N5) is the brightest new detection, with R 59F ¼ 8:8 nd n estimted distnce of 8.5 pc. CCD photometry from two nights indictes TABLE 4 Distnce Estimte Sttistics for New SCR Systems Proper Motion d 10 pc 10 pc < d 25 pc d > 25 pc 1B0 yr þ 0 0þ 0 2þ 4 1B0 yr 1 > 0B8 yr þ 0 3þ 0 2þ 1 0B8 yr 1 > 0B6 yr þ 1 4þ 7 25þ 23 0B6 yr 1 > 0B4 yr þ 1 8þ þ 93 Totl... 3 þ 2 15þ þ 121 Note. Excluding white dwrfs nd new wide compnions; the first number is from Pper XII, nd the second number is from this pper. V J ¼ 10:21, R KC ¼ 9:21, nd I KC ¼ 8:03, confirming tht it is very bright object. These vlues, when combined with the 2MASS JHK s mgnitudes, yield distnce estimte of 9.4 pc using the reltions in Pper X. SCR ( ¼ 0B426 yr 1 t position ngle 300N2) is common proper motion compnion to LTT 2976, which hs ¼ 0B361 yr 1 t position ngle 303N7 nd trigonometric prllx of 0B B00157 ¼ 19:5 0:6 pc (Perrymn ). The seprtion of the two strs is (projected seprtion 8000 AU) t position ngle 208N9. SCR is probbly white dwrf, for which we estimte distnce of 16.2 pc. This distnce is consistent with the trigonometric distnce mesured for LTT 2976 within the 20% errors of the white dwrf distnce reltions. Although the sizes of the proper motions do not mtch perfectly, the better determined position ngles re consistent, so we conclude tht the two strs form system. SCR ( ¼ 0B430 yr 1 t position ngle 229N0) is common proper motion compnion to CD ( ¼ 0B436 yr 1 t position ngle 228N1), for which Hipprcos mesured trigonometric prllx of 0B B00241 ¼ 25:0 1:5 pc (Perrymn 1997). The seprtion of the two strs is t position ngle 123N5. The distnce estimte for SCR , 31.2 pc, is consistent with the Hipprcos distnce for CD , within the 26% errors of the plte mgnitude distnce reltions, nd the proper motions re mtch. We conclude tht the two strs form system. SCR ( ¼ 0B447 yr 1 t position ngle 243N2) is probble common proper motion compnion to L ( ¼ 0B285 yr 1 t position ngle 235N0; NLTT Ctlogue) for which there is no trigonometric prllx vilble. The seprtion of the two strs is t position ngle 159N0. The sizes of the proper motions do not mtch well, but the position ngles re fir mtch. Given the incomplete informtion in the NLTT (no photogrphic R mgnitude), presumbly becuse of the very crowded field, the proper motion for L is suspect. In fct, we cnnot estimte distnce for L becuse it is blended on severl pltes, precluding relible plte mgnitudes. We tenttively conclude tht the two strs form system. SCR AB ( ¼ 0B540 yr 1 t position ngle 231N0) is close double system with seprtion 2B5 t position ngle 266N2, determined using frmes cquired during CTIOPI. The mgnitude differences re 0.56, 0.49, nd 0.37 mg t VRI, respectively. SCR AB ( ¼ 0B402 yr 1 t position ngle 227N4) is common proper motion pir with seprtion of t position ngle 234N0. While investigting the primry, the B component ws noticed on imges extrcted from ll four vilble 2 Informtion is vilble from the VizieR Online Dt Ctlog, ctlog number 1239.

11 1668 SUBASAVAGE ET AL. pltes; however, it is blended with other sources in ll four cses, so no relible plte photometry or distnce estimte is vilble. SCR is one of nine objects with distnce estimte in excess of 200 pc nd the only one not flgged s subdwrf cndidte. The R 59F J color is too blue for the conservtive subdwrf cndidte selection criteri. While this object my be subdwrf, dwrf contmintion t these colors wrrnts exclusion from the subdwrf cndidte list. SCR ( ¼ 0B446 yr 1 t position ngle 133N7) is common proper motion compnion to LTT 8495 ( ¼ 0B417 yr 1 t position ngle 134N1), for which there is no trigonometric prllx vilble. The seprtion of the two strs is t position ngle 168N0. The proper motions re consistent, indicting tht the two strs lmost certinly form system. However, from plteþ JHK s photometry, distnce estimtes re 25.9 nd 78.5 pc for LTT 8495 nd SCR , respectively, which indictes tht if the two re pir, LTT 8495 is likely to be n unresolved multiple. 6. DISCUSSION One of the primry motivtions for high proper motion (HPM) surveys is, of course, the promise of detecting new nerby strs. The new nerby discoveries re typiclly red dwrfs nd, occsionlly, white dwrfs. The output lists of sources detected, once culled for flse hits, lso include subdwrfs of very high intrinsic velocity tht re generlly not s ner s their min-sequence counterprts but re nevertheless interesting in their own right s trcers of the Glctic hlo popultion. Listed in Tble 4 is summry of the number of SCR systems with distnce estimtes within ech of our two trget horizons (10 nd 25 pc) nd beyond. New common proper motion objects tht re compnions to known objects re not included in the counts nor re probble white dwrfs (becuse their distnce estimtes require different reltions thn pplied here). The two numbers given for ech entry represent the number of SCR systems reported in Pper XII nd this pper, respectively. In most cses the numbers re comprble, which reflects the fct tht lthough much of the sky serched in this pper hs lredy been serched by Gicls et l. (1971, 1978) nd Luyten (1979, 1980), there is significntly more sky covered in this pper thn in Pper XII. In totl, we hve found 43 new cndidte systems within 25 pc of the Sun. There remin severl likely subdwrfs with overestimted distnces tht my fll in closer bins thn indicted in Tble 4. Perhps the most surprising result of this survey is the discovery tht the slowest proper motion (0B6 yr 1 > 0B4 yr 1 ) contins the lrgest number (26) of new cndidtes for systems within 25 pc. In fct, we hve found equl numbers of 10 pc cndidtes with >1B0yr 1 s we hve with 0B6 yr 1 > 0B4 yr 1. As pointed out in Pper XII, the presence of so mny new nerby strs with reltively low proper motions hints tht there my be lrge numbers of even slower moving strs tht remin hidden in the solr neighborhood. Thus, serches for nerby strs buried in lrge smples with smller proper motions re wrrnted, prticulrly given the vilbility of lrge photometric dtbses tht llow the derivtion of ccurte distnce estimtes when opticl nd infrred dt re combined, such s done here. In summry, we hve reveled totl of 299 new SCR proper-motion systems in the southern sky. Of these, 148 hve 0B5 yr 1, mking them new members of the clssic LHS smple. Among the new discoveries, we nticipte tht most re min-sequence M dwrfs, t lest nine re white dwrf cndidtes, t lest five re new binry systems, nd 64 re K- or M-type subdwrf cndidtes. Seven dditionl proper-motion compnions to previously known HPM strs were lso found. Five of the nine white dwrf cndidtes re nticipted to be within 25 pc. Worthy of note re the eight new SCR strs brighter thn R 59F ¼ 12, six of which hve 0B5 yr 1, hinting t the possibility of reltively bright nerby strs tht hve not yet been identified. All three sets of strs white dwrfs, red dwrfs, nd subdwrfs provide importnt contributions to these intrinsiclly fint, neglected smples. Undoubtedly, objects finter thn our survey cutoff of R 59F ¼ 16:5remintobefound,swells smll number of strs meeting our survey criteri tht fell in crowded regions or were simply missed becuse of the stringent limits required for SCR str vercity. Finlly, we re delighted to hve discovered during the SCR survey five new systems tht re likely new members of the RECONS 10 pc smple nd re ctively determining ccurte prllxes for them, s well s for mny of the 38 other SCR systems within 25 pc, vi our prllx progrm in Chile, CTIOPI. Finder chrts re given in Figure 5 for ll of the new systems reported here, s well s for the four new wide compnions. Funding for the SuperCOSMOS Sky Survey (SSS) is provided by the UK Prticle Physics nd Astronomy Reserch Council. N. C. H. would like to thnk collegues in the Wide Field Astronomy Unit t Edinburgh for their work in mking the SSS possible; prticulr thnks go to Mike Red, Sue Tritton, nd Hrvey McGillivry. The uthors would like to thnk the referee for constructive comments iding the clrity of this pper. The RECONS tem t Georgi Stte University wishes to thnk NASA s Spce Interferometry Mission for its continued support of our study of nerby strs. This work hs mde use of the SIMBAD, VizieR, nd Aldin dtbses, operted t the CDS in Strsbourg, Frnce. We hve lso used dt products from the Two Micron All Sky Survey, which is joint project of the University of Msschusetts nd the Infrred Processing nd Anlysis Center, funded by NASA nd NSF.

12 Fig. 5. Finder chrts for the 152 new SCR systems nd four wide compnions to known HPM strs. Ech finder chrt is 5 0 on side, with north up nd est to the left. The observtion epoch for ech frme is given. The bndpss for ech finder chrt is R 59F.

13 Fig. 5. Continued 1670

14 Fig. 5. Continued 1671

15 Fig. 5. Continued 1672

16 Fig. 5. Continued 1673

17 Fig. 5. Continued 1674

18 Fig. 5. Continued 1675

19 Fig. 5. Continued 1676

20 Fig. 5. Continued 1677

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