Appendix

A. Description of observed stars

A.1. Normal giants

In recent work it has been shown that the mass loss rate in the red giant branch appears to be higher than previously thought (Zuckerman et al. 1995). Most of the objects observed in our survey are normal giants showing a far-infrared emission typical of circumstellar dust. In Table 2 (click here) we list the 20 normal giants showing a faint Li line. The 57 normal stars, with no Li line, are listed in Table 3 (click here).

 

IRAS name identification S.T. m_V W(Li) W(Li)/W(Ca)

01504+5953 DO24938 M3 0.05 0.32

02401+8139 SAO432 K2 8.5 0.10 0.43

03396+5111 SAO24181 K7 8.5 0.08 0.36

05505+0932 SAO113234 K2 8.1 0.03 0.13

07365-1923 0.10 0.20

12100-6952 S Mus 0.01 0.05

13027-6024A 0.09 0.08

14262-5805 CGCS2163 0.04 0.33

16583-0408 BSC6318 K4I 4.8 0.06 0.28

17464+6739 0.01 0.25

18232+0800 BSC6902 G8I 5.6 0.01 0.05

18416+0232 0.03 0.30

18453+1949 SAO104107 K3 8.0 0.06 0.23

19019-1039A 0.01 0.06

19246+2826 DY Cyg 0.01 0.48

19425+4939 SAO48778 K0 7.6 0.06 0.32

19575+7618 SAO9582 MA 0.03 0.18

20550+6418 0.06 0.29

21121+4920 DO39334 0.03 0.25

21196+4648 SAO50754 K3I 7.8 0.01 0.35

We use "CGCS" to identify an object in the General Catalogue of Cool Carbon Stars (Stephenson 1989, also designed by GCGCS); "DO": Dearborn Observatory Catalogue of Faint Red Stars; "BSC": Bright Star Catalogue.  

 

IRAS name identification S.T. m_V

01068+5428 SAO 2204 K0 7.0

03421+0146 SAO 111338 K2 8.0

03557+0118 SAO 111532 K5 7.2

05074-0037 SAO 131834 K0 6.3

05461-0148 SAO 132556 K2 7.7

07150-4034 SAO 218604 G0 7.3

07310-1918 SAO 153062 K0 5.0

08158-3554 SAO 199051 K5 6.5

08175-4602 SAO 219783 K0 7.0 08389-4145

09184-4457 SAO 221077 K0I 6.5

09270-5855 SAO 237018 8.8 09337-5301

11418-5809 SAO 239336 K2 7.5

12392-5429 SAO 240165 K5I 6.5 12401-6224 13027-6024B

13086-5643 CV Cen

13301-5516B ER Cen

13301-5516C ER Cen 13399-5605

13432-1210 SAO 158152 K0 5.7

14121-5155 CGCS2151

14130-5305 SAO 241582 K5 7.7

14244-5448 SAO 241733 MA 8.5 14311-5311 14359-5855

16094-4600 GCSS502 A 16103-5321

16111-3253 SAO 207480 K0I 6.0

16255-5738 SAO 243874 K0 6.0

16553-1417 SAO 160195 K2 7.2 17158+1323

17388-4333 SAO 228311 K2 7.3

17402+5150 SAO 30522 K0 6.0

17477-2146 SAO 185836 K5

17499-1352 GCVS9795

17547+0012 SAO 122953 K5 8.9 18048-0636 18073+0032

18120-0237 SAO 142176 K5 7.8

18383+0708 DO5000 K5 9.0 18405-1732 18420-1834

18500+1428 SAO 104203 K0 6.5 19049+1702

20001+4358 SAO 49105 M0 7.2 20027+2534

20035-0413 SAO 144062 K0 6.5 20052+3551 20227+5605

20375+2925 DO19235

21181+5406 CCS3011

21217-8501 SAO 258899 K2 6.4

22209-0726 SAO 146062 G6I 6.0

23579+5916 BSC9079 G9I 6.1

We use "GCVS" to identify an object in the General Catalog of variable stars.  

de la Reza et al. (1997) argue that the presence of dust around normal-Li giants is connected to a Li depletion occurring faster than the shell dissipation. The normal giants are located apart from the LRG, the latter being redder. We note that in the IRAS diagram "box" surveyed in the present work this effect is not observed.

A.2. Cool giants

A large group of stars with strong molecular bands is listed in Table 4 (click here). The bandheads are mainly at 665.1, 668.0, and 671.7 nm, corresponding to TiO bands.

 

IRAS name identification S.T. m_V note

00135+4736 DO23016 ab

06262+0727 ab

06319+0500 SAO 114079 MB 7,1 c

07081-2248 SAO 173118 M ab

07417-3343 SSSC0741-337 ab

08194-4509 a

08234-3536 GCSS 311 b

08249-4425A ab

08346-5626 b

08577-4003 b

10109-5357 a

10551-5250 GCSS 418 a

11252-5510 ab

11396-5547 UMSA A3III a

11516-3935 UMSA M3III a

12200-5620 a

12454-7411 a

13057-7115 a

13301-5516A ER Cen c

13552-5529 a

13575-5529 c

14066-5657 a

14244-5448 SAO 241733 MA 8.5 ab

14528-5134 ab

15353-6325 c

15363-4918 c

15591+8313 SAO 2638 9.0 a

16166-5426 c

16237-5627 b

16345+0728 a

17050+1449 DO15795 ab

17167+1517 SAO 102733 M 9.1 b

17283-4240 c

17462-0907 c

18060-0740 a

18160-2636 a

18338+0911 DO4926 a

18405-1732 c

19043+2021 abc

19066-0624 ab

19136+0423 b

19316+1636 a

19468+4019 c

19490+3706 V1294 Cyg c

19579+2518 ab

20061+4131 V426 Cyg a

20062+0451 SAO 125493 M0 9.0 a

20283+7414 DO19235 ab

20333+3127 b

20447+3808 ab

21440+5113 ab

22131+5557 c

23115+5651 ab

23591+6154 DO 43982 ab

We use "SSSC" to identify an object in the IRAS Small Scale Structure Catalog; "UMSA": University of Michigan Spectral Atlas; "2 I": Two Micron Sky Survey Improved.
Notes: Detected spectral lines: a) , b) Ca I, c) Li I.  

A.3. Other objects

A few stars, listed in Table 5 (click here), show features not typical of the groups above discussed and we classified them as spurious objects. Most of them show a large absorption line, that could represent early-type stars. We have detected 4 stars with faint emission line, which we tentatively classify as possible weak T Tauri stars. We also detected 2 Carbon stars.

 

IRAS name identification S.T. m_V note

05142+7910 SAO 5496 F8 5.1 a

06444+0038 CGCS 580 c

06489-0511 CGCS 597 c

08197-3447 CGCS 1143 b

08217-4518 CGCS 1158 d

08249-4425B a

13301-5516D ER Cen a

15053-5322 CGCS 2214 d

17275-1016 a

18339-1323A b

18339-1323B a

18587+0947 a

19019-1039B a

19136+2127 d

19160+4641 d

19235+1054 d

19263+1214 a

19337+1620 a

19431+3014 a

19572+5157A CM Cyg b

19572+5157B CM Cyg N d

21270+4100 b

23481+6154 a

Notes: a) large absorption, b) emission, c) Carbon star, d) other.  

A.4. Comments on individual objects

IRAS 16161-1445 (HD 146850) - In Castilho et al. (1995) we carried out a detailed analysis of this star and found , and solar ratios of elements O,Mg, Ca, Ti relative to Fe. This star is a typical disk star.

IRAS 07559-5859 (HD 65750) - This (Pesce et al. 1989) oxygen-rich star is very interesting because of its large (3-4 arcmin) dust and gas envelope. Reimers (1977) estimated a /year mass loss rate, and an envelope mass of . Witt & Rogers (1991) estimated that this mass loss rate is not enough to form the observed envelope and they proposed that a past and more efficient mass loss event occurred about 32000 years ago. Its evolutionary status is not well defined due to the large uncertainties in the mass and luminosity determinations. Probably HD 65750 is at the base of the AGB.

The presence of this large envelope confirms our previous suggestion (Gregorio-Hetem et al. 1993) that the Li-rich giants are associated with circumstellar dust and gas envelopes emitting mostly in the infrared, and that this characteristic could be related with the high Li abundances (Castilho 1995; de la Reza et al. 1996).

  
Figure 3: I band image of HD 65750, showing the large envelope . North is up and West is to right

In Fig. 3 (click here) we present an I band CCD image of HD 65750, showing its large envelope (IC 2220). The image was obtained with a 60 s. exposure at the 60 cm B&C telescope at LNA (Brazil).

IRAS 10204-6135 (HD 90082) - Although the Li line doublet in this star is comparable to the Ca I line (), the molecular lines in this region do not permit a good estimation of the .

IRAS 19012-0747 and IRAS 19038-0026 - We found no identification for the optical counterparts of these two IRAS sources and no previous work on then. Both seem to be K stars. The ratio for IRAS 19012-0747 is the largest of our sample.

IRAS 18241-1443 (GCSS 577) - Chen & Kwok (1993) used this star in their circumstellar material study. It was identified as a S star by Kershbaum & Hron (1992). Its low resolution IRAS spectrum shows no peculiar features in the range (Olnon & Raimond 1986).