ISOPHOT Polarimetry--L1157 Region

Note: The information on this page was contributed and complied by Alyssa Goodman.

Goal is to make an ISO polarization map that shows the magnetic field structure in the immediate and wider vicinity of the L1157 YSO/Outflow/Core system. The southern portion of the inner outflow is shown in this figure, from Zhang et al. 1995.

There are four sets of positions to do in the L1157 region:

Note: "OFF" positions are listed as X10 and X11 at the bottom of this page. Positions 5 and 6 in the first map below may also be usable as OFFs.

Grid:

In addition to the positions spefically listed (with number or letter/number designations below), we should do a grid of positions, oriented N-S, covering the (inner) part of the outflow. The grid should be at least 2 x 2 pointings, but should preferably be 3x3, 2x3 or3x4 (with the longer direction north-south in all cases). The center of the grid should be on or near 20h 39m 06.6s; 68deg 02' 13.2" (J2000; which is close to postion number 4 below.

Please assign whatever sourcenames you like to the grid positions. I've assigned unique letter/number names to the other positions below. You can precede all these codes with "L1157" for clarity.

Positions "Along" the Dark Cloud:

1.1 deg x1.1 deg 100 micron image

numbers run from left to right in above image

1. RA = 310.622211 DEC = 67.620527 brightness = 16.49 MJY/SR band = 100 RA = 20h42m29.33064s DEC = +67d37m13.8972s (B1950)

2. RA = 310.418673 DEC = 67.718538 brightness = 15.75 MJY/SR band = 100 RA = 20h41m40.48152s DEC = +67d43m06.7368s (B1950)

3. RA = 310.085317 DEC = 67.764912 brightness = 15.47 MJY/SR band = 100 RA = 20h40m20.47608s DEC = +67d45m53.6832s (B1950)

4. RA = 309.679524 DEC = 67.859570 brightness = 35.64 MJY/SR band = 100 RA = 20h38m43.08576s DEC = +67d51m34.4520s (B1950)

5. RA = 309.007847 DEC = 67.923664 brightness = 9.052 MJY/SR band = 100 RA = 20h36m01.88328s DEC = +67d55m25.1904s (B1950)

6. RA = 308.735316 DEC = 67.968471 brightness = 9.435 MJY/SR band = 100 RA = 20h34m56.47584s DEC = +67d58m06.4956s (B1950)

Cloud's "environment":

1.1 deg x1.1 deg 100 micron image, numbers on plot correspond to "E" numbers below

E1: RA = 310.632509 DEC = 67.445901 brightness = 13.69 MJY/SR band = 100 RA = 20h42m31.80216s DEC = +67d26m45.2436s (B1950)

E2: RA = 310.610250 DEC = 67.820152 brightness = 12.6 MJY/SR band = 100 RA = 20h42m26.46000s DEC = +67d49m12.5472s (B1950)

E3: RA = 310.394388 DEC = 68.067929 brightness = 13.44 MJY/SR band = 100 RA = 20h41m34.65312s DEC = +68d04m04.5444s (B1950)

E4: RA = 310.053062 DEC = 67.365084 brightness = 13.63 MJY/SR band = 100 RA = 20h40m12.73488s DEC = +67d21m54.3024s (B1950)

E5: RA = 309.903458 DEC = 68.312306 brightness = 13.03 MJY/SR band = 100 RA = 20h39m36.82992s DEC = +68d18m44.3016s (B1950)

E6: RA = 309.183574 DEC = 67.576995 brightness = 13.6 MJY/SR band = 100 RA = 20h36m44.05776s DEC = +67d34m37.1820s (B1950)

E7: RA = 308.762933 DEC = 68.244043 brightness = 14.87 MJY/SR band = 100 RA = 20h35m03.10392s DEC = +68d14m38.5548s (B1950)

E8: RA = 308.414814 DEC = 67.461876 brightness = 15.03 MJY/SR band = 100 RA = 20h33m39.55536s DEC = +67d27m42.7536s (B1950)

General L1157 Region:

4.25 deg x4.25 deg 100 micron image

Numbers go from bottom of image along "snake" then top cross of two "offs" shown, then the one below that.

X1. RA = 309.898777 DEC = 66.914049 brightness = 19.82 MJY/SR band = 100 RA = 20h39m35.70648s DEC = +66d54m50.5764s (B1950)

X2. RA = 309.812329 DEC = 67.162347 brightness = 17.16 MJY/SR band = 100 RA = 20h39m14.95896s DEC = +67d09m44.4492s (B1950)

X3. RA = 310.312492 DEC = 67.368008 brightness = 13.64 MJY/SR band = 100 RA = 20h41m14.99808s DEC = +67d22m04.8288s (B1950)

X4. RA = 310.555075 DEC = 67.644908 brightness = 16.33 MJY/SR band = 100 RA = 20h42m13.21800s DEC = +67d38m41.6688s (B1950)

X5. RA = 310.085317 DEC = 67.764912 brightness = 15.47 MJY/SR band = 100 RA = 20h40m20.47608s DEC = +67d45m53.6832s (B1950)

X6 (L1157). RA = 309.679524 DEC = 67.859570 brightness = 35.64 MJY/SR band = 100 RA = 20h38m43.08576s DEC = +67d51m34.4520s (B1950)

X7. RA = 308.359327 DEC = 68.235692 brightness = 17.24 MJY/SR band = 100 RA = 20h33m26.23848s DEC = +68d14m08.4912s (B1950)

X8. RA = 307.915517 DEC = 68.450610 brightness = 16.76 MJY/SR band = 100 RA = 20h31m39.72408s DEC = +68d27m02.1960s (B1950)

X9. RA = 307.850774 DEC = 68.799505 brightness = 15.76 MJY/SR band = 100 RA = 20h31m24.18576s DEC = +68d47m58.2180s (B1950)

X10 (off 1). RA = 306.106127 DEC = 68.070610 brightness = 8.128 MJY/SR band = 100 RA = 20h24m25.47048s DEC = +68d04m14.1960s (B1950)

X11 (off 2). RA = 306.157292 DEC = 67.871907 brightness = 9.061 MJY/SR band = 100 RA = 20h24m37.75008s DEC = +67d52m18.8652s (B1950)

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