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2 Observations

The observations were made in several runs from 1999 January 30 to August 25 with the 32-m Torun radio telescope. We used a dual-channel cryogenically cooled HEMT receiver to measure simultaneously two opposite circular polarizations. Typical system temperature was 60 K on cold sky. The backend was a 214-channel autocorrelation spectrometer operating in 2-bit mode. We used its two parts of 4096 channels each with a bandwidth of 4 MHz, yielding a velocity resolution of 0.044 km s-1 and a velocity coverage of 180 km s-1. The radial velocities were measured with respect to the Local Standard of Rest. The band-centre velocity was generally chosen as 0 km s-1, but for the region $18^{\rm h} \le \alpha \le 19^{\rm h}$ the velocity of 40 km s-1 was set. The absolute radial velocity may be a subject of an error of $\pm$0.4 km s-1 due to the use of experimental software of a new autocorrelator. The data were taken in the total-power position switching mode. The half-power beamwidth of the telescope was 5.5 arcmin at 6.7 GHz. The pointing checks and corrections were regularly done on strong point continuum sources. It was found that rms pointing errors were less than 25 arcsec in our observations.

The calibration was achieved by injecting a signal from a noise diode of known temperature into the system, at the start of each integration. The noise diode was calibrated against the extragalactic sources 3C 123 and Vir A, adopting the flux densities from Ott et al. (1994). Because the telescope gain versus elevation varies less than 2% (Katarzynski 1997), no corrections were applied to our spectra. The accuracy of the absolute flux density calibration was commonly better than 15%.

The data were reduced using the standard procedures. The instrumental baseline was fitted using the line emission-free channels. The $3\sigma$ noise level after 14 min on-source integration and averaging the two polarizations was typically 1.5 to 1.9 Jy. Hanning smoothing was only applied to noisy spectra. To confirm the reality of new detections we reobserved all of them with the same setup of spectrometer as during the initial search. Tentative detections were observed for a longer integration time of 28 min. We did not verify the positions of the detected masers, but if spectra of identical shapes and velocities were seen in several neighbouring IRAS positions, the observations were repeated to find the strongest source that is only considered as the detection in this paper. The maser profiles were frequently complex, therefore, we read off the line parameters using the cursor rather than fitting Gaussian components.

The targets were selected from the IRAS Point Source Catalog (1985). All of them satisfied the following criteria: (1) F60>100 Jy, (2) F60 > F25 and (3) $\delta > -20^{\circ}$, where F25 and F60 are the flux densities at 25 and $60\,\mu$m respectively. No restrictions on the measurement qualities of infrared flux densities were imposed. The resulting sample included 1411 objects of which 1399 were searched for methanol maser emission.

 
Table 1: IRAS objects with the 6.7 GHz methanol maser emission
IRAS $\Delta V$ $V_{\rm p}$ $S_{\rm p}$ $S_{\rm i}$ Epoch Ref.
  (km s-1) (km s-1) (Jy) (Jy km s-1)    
00338+6312 -27, -21 -22.4 14 7.6 Feb. 10
00494+5617 -37, -27 -29.1 24 19.5 Apr. 11
02232+6138 -48, -41 -44.6 3741 7602.0 Jun. 2
02455+6034 -46, -44 -45.1 21 11.1 Feb. 8
05274+3345 0, 6 2.1 94 56.8 Mar. 4
05358+3543 -16, -11 -13.6 256 198.6 Jul. 2
05382+3547 -25, -24 -24.1 7.5 3.0 Jan. 1
05480+2545 -16, -4 -4.8 18 19.3 Mar. 11
06053-0622 9, 13 10.5 166 155.7 Aug. 2
06055+2039 3, 6 5.5 17 10.3 Jul. 2
             
06056+2131 9, 12 9.2 19 11.7 Mar. 6
06058+2138 8, 12 10.4 553 461.5 Aug. 2
06061+2151 -9, -4 -5.5 4.8 3.6 Jul. 1
06099+1800 2, 7 5.1 64 48.8 Mar. 2
06117+1350 14, 17 15.3 68 37.9 Jul. 2
07299-1651 21, 24 22.6 217 100.5 Jul. 3
18056-1952 59, 77 72.5 19 68.1 Jul. 2
18056-1954 70, 75 73.4 9.8 23.3 Aug. 6
18061-1927 14, 18 16.8 4.5 8.2 Jul. 1
18067-1927 23, 25 23.9 15 10.6 May 5
             
18072-1954 -9, 0 -8.0 3.4 2.9 May 6
18089-1732 29, 40 38.9 61 85.2 May 2
18090-1832 105, 112 107.4 77 97.1 May 2
18092-1842 39, 44 42.6 49 41.2 May 2
18094-1840 46, 49 46.8 2.3 2.4 May 6
18096-1821 47, 54 48.7 9.2 15.8 Jul. 1
18097-1825 15, 30 19.1 7.9 20.3 May 2
18099-1841 60, 61 60.2 2.3 1.2 Mar. 9
18102-1800 22, 27 24.4 13 23.1 Mar. 11
18108-1759 50, 61 57.7 264 544.2 Mar. 2
             
18110-1854 30, 44 32.1 41 61.3 Mar. 2
18111-1746 58, 61 58.7 8.3 9.4 Jul. 1
18111-1729 48, 49 48.5 6.4 3.0 Apr. 1
18117-1753 35, 41 39.8 242 256.7 Jul. 2
18126-1705 42, 52 51.9 3.4 3.5 Aug. 1
18128-1640 4, 17 15.1 135 152.3 Jul. 11
18134-1942 4, 17 6.2 116 178.8 May 5
18141-1626 26, 28 27.0 3.0 1.2 Mar. 1
18141-1615 22, 28 24.8 2.9 5.3 Mar. 9
18144-1723 47, 52 51.0 33 49.8 Mar. 10
             
18151-1208 27, 29 27.7 65 40.0 Apr. 7
18155-1554 45, 46 45.8 3.1 1.1 Jul. 1
18174-1612 20, 23 20.9 19 8.8 May 2
18181-1534 -5, -2 -3.4 33 14.7 Jul. 1
18182-1433 56, 69 61.6 24 38.3 May 2
18184-1449 49, 53 52.1 10 10.1 Jul. 1
18193-1411 90, 91 90.8 1.3 0.7 Aug. 1
18196-1331 20, 21 20.5 20 4.9 Jun. 3
18207-1311 45, 57 55.2 3.9 8.9 Jul. 1
18208-1306 55, 59 57.9 11 7.4 Jun. 1



 
Table 1: continued
IRAS $\Delta V$ $V_{\rm p}$ $S_{\rm p}$ $S_{\rm i}$ Epoch Ref.
  (km s-1) (km s-1) (Jy) (Jy km s-1)    
18217-1252 48, 50 49.2 14 7.5 Aug. 2
18220-1241 76, 83 80.2 22 34.5 Aug. 1
18224-1228 38, 39 38.2 3.7 1.6 Aug. 1
18224-1311 73, 80 75.2 13 26.3 May 1
18232-1154 18, 25 20.7 15 21.0 May 2
18236-1241 41, 44 41.1 2.3 1.9 Jul. 11
18236-1205 24, 29 26.3 6.7 10.1 Jul. 9
18244-1155 48, 58 56.3 8.6 8.0 Aug. 6
18249-1116 68, 76 71.4 94 74.1 Jun. 2
18251-1154 41, 44 43.6 10 11.2 Jun. 1
             
18264-1152 46, 47 46.8 2.3 1.3 Aug. 1
18265-1517 14, 19 14.6 23 14.7 Aug. 9
18277-1517 19, 24 23.3 3.7 2.9 Aug. 1
18278-1009 115, 119 116.6 14 12.2 Jun. 1
18278-0936 46, 54 53.4 5.5 5.4 Aug. 1
18282-0951 20, 22 20.4 2.9 1.8 Aug. 2
18282-1024 85, 92 88.8 3.7 5.9 Jul. 1
18290-0924 79, 85 79.7 12 6.8 Aug. 5
18302-0928 28, 39 29.0 3.2 5.2 Aug. 1
18305-0826 71, 77 74.1 17 31.0 Jul. 1
             
18305-0758 74, 78 76.4 9.6 8.1 Mar. 1
18310-0825 81, 89 87.4 12 9.2 Mar. 5
18316-0602 38, 44 41.9 178 69.5 Apr. 7
18317-0859 71, 84 75.0 29 59.6 Jul. 1
18317-0845 63, 65 64.1 4.4 4.5 Jun. 5
18319-0834 95, 108 102.6 40 92.8 Aug. 2
18321-0843 63, 76 63.8 2.2 1.5 Aug. 1
18321-0854 72, 83 81.8 12 43.4 Aug. 1
18321-0820 76, 87 82.1 11 30.0 Aug. 1
18322-0721 103, 111 106.2 15 26.0 Jul. 1
             
18324-0737 107, 120 109.9 4.6 7.4 Aug. 2
18324-0855 73, 83 75.2 9.2 27.0 Aug. 1
18324-0820 75, 85 79.0 9.2 26.6 Aug. 5
18326-0802 64, 72 70.9 17 12.7 Aug. 1
18326-0751 17, 19 17.7 40 24.1 Aug. 1
18334-0733 108, 116 114.4 29 24.6 Jul. 7
18335-0713 106, 115 113.0 97 141.6 Jul. 2
18337-0707 107, 118 109.3 13 16.1 Jul. 1
18341-0727 111, 114 113.1 3.5 2.5 Jul. 11
18345-0641 93, 100 94.7 8.0 12.6 Jul. 7
             
18353-0628 89, 101 95.5 364 346.7 Jul. 9
18361-0627 89, 94 91.2 20 26.0 Jul. 5
18372-0537 106, 108 107.1 5.9 2.5 Jul. 1
18372-0541 17, 25 24.6 13 13.1 Jul. 1
18379-0500 34, 37 34.9 21 13.9 Aug. 11
18379-0546 102, 115 103.2 19 20.4 Jul. 7
18391-0504 91, 102 99.7 23 35.8 Aug. 1
18392-0436 108, 113 111.8 1.9 2.6 Jul. 1
18402-0403 67, 81 71.1 3.4 8.0 Jul. 1
18403-0417 94, 104 100.8 56 30.6 Jul. 6



 
Table 1: continued
IRAS $\Delta V$ $V_{\rm p}$ $S_{\rm p}$ $S_{\rm i}$ Epoch Ref.
  (km s-1) (km s-1) (Jy) (Jy km s-1)    
18403-0445 97, 98 97.9 3.0 1.5 Jul. 1
18416-0420 79, 93 80.7 62 54.0 May 5
18421-0348 81, 93 83.9 58 125.1 Apr. 2
18434-0242 95, 106 95.8 197 288.4 Feb. 2
18438-0222 32, 51 36.7 11 19.0 Mar. 1
18440-0148 104, 111 104.9 3.0 2.0 Aug. 2
18441-0153 47, 49 48.9 19 10.4 May 6
  76, 88 87.5 8.2 19.7 May  
18441-0134 78, 84 80.8 4.5 9.3 May 1
18443-0231 100, 114 108.1 18 26.6 May 2
             
18446-0209 40, 48 42.4 4.8 6.0 Aug. 2
18447-0229 108, 114 112.1 3.9 5.6 Aug. 6
18448-0146 98, 110 101.5 33 60.5 Aug. 5
18449-0158 87, 93 91.5 23 33.5 Aug. 6
18449-0115 91, 105 95.4 10 31.4 Aug. 5
18450-0205 85, 92 87.6 43 27.7 Aug. 6
18450-0200 85, 94 88.1 50 71.2 Aug. 6
18452-0141 15, 17 16.1 6.5 4.0 Aug. 5
18454-0156 101, 108 101.1 4.3 4.4 Aug. 2
18454-0136 40, 48 40.8 2.9 1.8 Aug. 1
             
18455-0149 73, 78 74.7 5.9 8.9 Aug. 1
18456-0129 102, 113 110.0 71 153.1 Aug. 2
18461-0113 95, 100 98.4 5.6 6.3 Aug. 1
18470-0050 92, 102 92.8 93 123.7 Aug. 7
18487-0015 28, 39 38.2 48 70.8 Jun. 2
18488+0000 89, 93 91.7 27 22.0 Jul. 7
18494+0002 95, 106 104.6 19 26.4 Mar. 6
18496+0004 72, 75 73.5 13 17.1 Mar. 2
18497+0022 96, 107 105.0 20 41.6 Aug. 11
18507+0121 55, 63 55.8 27 25.8 Jul. 5
             
18507+0110 55, 63 57.9 18 20.9 Aug. 2
18508+0052 58, 63 59.0 3.9 3.5 Aug. 1
18512+0029 58, 64 62.6 68 109.1 Aug. 1
18515+0157 40, 47 44.1 35 27.9 Aug. 2
18517+0437 40, 52 41.1 279 161.5 Aug. 5
18527+0301 70, 85 73.0 19 32.7 Aug. 1
18556+0136 26, 37 28.9 64 91.8 Jul. 2
18566+0408 78, 87 83.7 6.6 10.7 Aug. 11
18572+0057 43, 48 46.9 31 67.2 Jul. 7
18577+0358 49, 63 62.6 5.7 19.7 Jul. 1
             
18592+0426 69, 71 69.4 2.3 3.2 Jul. 1
18592+0108 40, 47 42.6 595 536.4 Jul. 2
19002+0654 5, 16 15.6 18 26.8 May 5
19012+0505 31, 34 32.3 5.4 3.9 Mar. 1
19031+0621 64, 81 74.0 18 39.4 Aug. 1
19035+0641 30, 36 31.0 15 6.5 Jun. 2
19048+0705 63, 64 63.4 3.7 1.7 Aug. 1
19049+0712 55, 58 57.1 3.2 3.4 Aug. 1
19078+0901 7, 22 9.1 31 87.1 Jun. 2
19092+0841 54, 57 54.8 10 7.2 Jun. 10



 
Table 1: continued
IRAS $\Delta V$ $V_{\rm p}$ $S_{\rm p}$ $S_{\rm i}$ Epoch Ref.
  (km s-1) (km s-1) (Jy) (Jy km s-1)    
19095+0930 39, 44 39.5 79 54.7 Jun. 2
19097+0847 58, 60 58.8 5.5 3.1 Jul. 1
19110+1045 57, 59 57.8 45 21.8 Jul. 2
19117+1107 57, 67 65.8 10 10.5 Jul. 2
19120+1103 55, 66 56.1 4.1 8.0 May 2
19120+0917 47, 53 47.4 34 25.5 May 5
19186+1440 -27, -10 -12.4 13 34.3 Jul. 1
19189+1520 -10, -2 -5.0 6.5 6.6 Jul. 1
19191+1538 26, 33 29.9 2.8 4.9 Jul. 1
19211+1432 58, 66 62.8 29 75.9 Jul. 1
             
19216+1429 51, 62 59.3 482 428.7 Jul. 2
19230+1341 34, 41 35.5 21 22.0 Jan. 7
19266+1745 9, 11 10.0 3.3 1.3 Jul. 1
19270+1750 23, 25 23.8 1.9 1.1 Aug. 1
19282+1814 18, 19 18.7 6.3 3.0 Jul. 1
19366+2301 31, 36 34.0 2.8 4.8 May 1
19410+2336 14, 28 17.3 34 54.9 Apr. 2
19437+2410 3, 4 3.6 4.1 1.2 Jul. 1
19589+3320 -27, -26 -26.5 9.8 4.9 Jul. 11
20062+3550 -4, 7 -2.5 10 6.3 Jul. 11
             
20081+3122 0, 16 15.1 109 44.8 Mar. 2
20110+3321 3, 11 10.7 5.3 3.2 Jun. 1
20126+4104 -8, -5 -6.1 38 18.3 Apr. 3
20198+3716 -11, 1 -2.9 39 39.4 May 2
20350+4126 -5, -4 -4.1 4.3 2.2 Jul. 11
21074+4949 -72, -68 -70.5 27 17.3 Jul. 1
21381+5000 -44, -40 -40.9 7.0 10.5 Jul. 11
21413+5442 -62, -61 -61.6 3.3 1.5 Jul. 1
22272+6358 -13, -9 -10.9 91 47.4 Jul. 11
22543+6145 -5, -1 -2.5 815 812.5 Mar. 2
             
22566+5830 -46, -45 -45.7 2.8 1.3 Jul. 1
23116+6111 -62, -48 -56.3 296 475.3 Jul. 2
23139+5939 -42, -37 -38.5 4.0 6.5 Jul. 1

Discovery reference: 1 - this paper, 2 - Menten (1991), 3 - MacLeod & Gaylard (1992),
4 - Gaylard & MacLeod (1993), 5 - Schutte et al. (1993), 6 - Caswell et al. (1995),
7 - van der Walt et al. (1995), 8 - Lyder & Galt (1997), 9 - Walsh et al. (1997),
10 - MacLeod et al. (1998), 11 - Slysh et al. (1999).



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