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PI: Cooke/Hsyu

Goal: We will take longslit spectroscopy of diffuse, blue smudges to measure the metallicity and the helium abundance of the H II regions.

Setup:

Number

Dichroic

Blue

Red

Wavelength Coverage

slit

binning

1

D560

600/4000

600/7500

B:3010-5600A, R:5500-8800A

0.7"

2x2

2

D560

600/4000

600/10000

B:3010-5600A, R:7700-11000A

0.7"

2x2

3

CLEAR

N/A

900/5500

R:4750-6850A

0.7"

2x2

Note: Setup 3 only needs to be a short exposure, to detect H-alpha, H-beta, and the [O III] doublet. Note: Until further notice, observations with Setup 2 will be pursued at another time.

Observing Procedure:

  1. Go to the coordinates of the offset star and rotate the slit to the required PA
  2. Align the offset star at the slit-B position.
  3. Apply the offset listed in the DELTA RA and DELTA DEC columns to go to the science target

  4. Expose

Necessary Calibrations: Please take arcs, biases, flats, and a flux standard with the same setup.

Conditions: Each target should have emission lines, so this project can still be done in poorer conditions. The target He I lines are weak, so increase the exposure times as necessary. As a guideline, the He I 6679 emission line (red arm in Setup 1) needs to be detected with at least 10 sigma confidence (i.e. a S/N >= 10) for the science goals to be achieved (Note: the flux ratio He I 6679 / Halpha ~= 0.01) and the [O III] 4363 line needs to be detected (blue arm in Setup 1 and 2). In addition, there are some brighter targets at the bottom of the target table (labeled priority 3).

Exposure time (Setup 1&2):

The total exposure time per target depends on the S/N of several lines. The typical (total) exposure time per target is 2 x 600s (red) and 4 x 260s (blue). Here is a step-by-step process for observing:

  1. Begin by observing a target for the listed exposure time.
  2. After read-out of the first exposure, start a second exposure of the target.
  3. Straight after you begin the second exposure, inspect the raw data of the first exposure.
  4. If the data show no obvious emission lines (e.g. H-alpha 6563A, or the [O III] doublet at 4959A/5007A), abort the second exposure and move to a new target.
  5. If the data show emission lines, please take at least 2 exposures in the red and 4 in the blue (total).
  6. Using the raw data from the first exposure, determine the number of exposures needed to obtain S/N >=10 in He I 6679 and a detection of [O III] 4363.

Exposure time (Setup 3):

Setup 3 will be used to stitch the LRIS b&r arms from Setup 1, and should only be a short exposure (red arm only), probably 2x120s is sufficient. We need to detect H-alpha, H-beta, and the [O III] doublet with this setup to achieve our science goals.

Target List: This is a list of targets. They are ranked by priority (see priority column), and then by RA. Here are some specifics:

  1. The first set of objects only need Setup 2&3 (a total of 20 mins exposure per target for setup 2 and 4 mins for setup 3).

  2. The second set of objects should be observed with Setup 1&2&3. If time doesn't permit, do Setup 1 only (corresponding to a total of 20 mins exposure per target), and move that object to the setup 2&3 section of the table.

  3. Most of the position angles are 0.0 degrees (i.e. the slit is aligned north-south). Non-zero PA's correspond to the position angle of the slit from north, heading east.

Finding charts for the targets are available here.


Target Name

Offset Star RA

Offset Star DEC

Target RA

Target DEC

DELTA RA (arcsec)

DELTA DEC (arcsec)

PA (deg)

Priority

Exp Time (s)

Notes

SETUP 1&3

J1005p3722

10 05 07.46

+37 20 50.2

10 05 12.15

+37 22 01.5

55.94"E

71.34"N

0.0

1

3600 (setup 1), 240 (setup 3)

J1056p3608

10 56 35.09

+36 09 51.1

10 56 40.35

+36 08 27.9

63.72"E

83.20"S

0.0

1

3600 (setup 1), 240 (setup 3)

J1204p5259

12 04 53.84

+53 00 31.2

12 04 59.62

+52 59 34.7

52.22"E

56.56"S

0.0

2

3600 (setup 1), 240 (setup 3)

J1356p3741

13 56 24.60

+37 40 24.2

13 56 26.26

+37 41 30.6

19.67"E

66.37"N

0.0

1

3600 (setup 1), 240 (setup 3)

J1641p0959

16 41 28.12

+09 59 41.2

16 41 25.17

+09 59 26.95

43.56"W

14.24"S

0.0

2

3600 (setup 1), 240 (setup 3)

currently unconfirmed if emission lines are present

J1751p4443

17 51 37.55

+44 44 55.9

17 51 37.11

+44 43 11.7

4.72"W

104.24"S

0.0

1

3600 (setup 1), 240 (setup 3)

currently unconfirmed if emission lines are present

SETUP 2&3

J0018p2345

00 18 59.94

+23 47 18.3

00 18 59.31

+23 45 40.3

8.65"W

98.00"S

0.0

1

1200 (setup 2), 240 (setup 3)

09Jan2016

J0214m0835

02 14 04.23

-08 37 02.7

02 14 01.93

-08 35 43.0

34.11"W

79.65"N

0.0

1

1200 (setup 2), 240 (setup 3)

10Jan2016

LeoP

10 21 44.64

+18 04 58.2

10 21 45.12

+18 05 16.8

6.84"E

18.6"N

0.0

1

1200 (setup 2 ONLY)

DDO68

09 56 46.63

+28 49 28.4

09 56 46.05

+28 49 43.8

7.62"W

15.40"N

0.0

2

1200 (setup 2 ONLY)

SETUP 1&2&3

J0757p4750

07 57 26.93

+47 50 45.5

07 57 33.93

+47 50 30.7

70.47"E

14.8"S

0.0

1

1200 (setup 1&2), 240 (setup 3)

10Jan2016

J0823p1754

08 23 27.50

+17 54 42.6

08 23 25.67

+17 54 56.0

26.12"W

13.4"N

0.0

1

1200 (setup 1&2), 240 (setup 3)

11Jan2016 (setup 1)

J0845p0131

08 45 30.69

+01 30 19.7

08 45 28.25

+01 31 27.9

36.59"W

68.2"N

0.0

1

1200 (setup 1&2), 240 (setup 3)

J0918p3527

09 18 29.41

+35 26 42.5

09 18 27.57

+35 27 19.7

22.48"W

37.2"N

0.0

1

1200 (setup 1&2), 240 (setup 3)

Keep for later

J2356m1928

23 56 50.13

-19 26 07.8

23 56 51.86

-19 28 06.5

24.47"E

118.7"S

0.0

3

1200

J0034p2702

00 34 20.60

+27 02 26.8

00 34 19.70

+27 02 07.9

12.02"W

18.90"S

0.0

3

1200

11Jan2016 (setup1)

J0102m0430

01 02 20.32

-04 29 20.1

01 02 24.04

-04 30 25.5

55.63"E

65.40"S

0.0

3

1200

11Jan2016 (setup1)

J0106p3235

01 05 59.83

+32 36 12.3

01 06 03.52

+32 35 31.9

46.63"E

40.40"S

0.0

3

1200

KCWI (no emission line BCDs)

J0202p3126

02 02 25.63

+31 26 01.83

02 02 26.61

+31 27 42.43

25.47"W

98.09"S

0.0

3

1200

object showed no emission lines on Shane+Kast; priority and exp time as available; Finder chart w/FOV, offset to FOV center here; SDSS; PanSTARRS

J0339m1213

03 39 57.53

-12 13 20.56

03 40 03.74

-12 14 31.14

87.48"W

64.92"N

0.0

3

1200

object showed no emission lines on Shane+Kast; priority and exp time as available; Finder chart w/FOV, offset to FOV center here; SDSS; PanSTARRS

XmPs (last edited 2017-10-20 18:01:01 by tiffanyhsyu)