README web version of /home/usg/OPS/MTS/readme_xml/readme_75067000

Principal Investigator Email Address

```
jwalsh@eso.org
```

Estimated Total Execution Time (hours, including overheads)

```
35hr 32m
```

General Description

Narrow band imaging of the spiral galaxy NGC300 to obtain a catalogue
 of its planetary nebulae. The strongest line is [O III]5007A and imaging in this
 line can be compared with a continuum band around 5500A, which has only weak lines,
 to reveal the PN. PN at the distance of NGC300 are unresolved from the ground and
 so are point sources; good seeing is an issue for these observations.
The strategy is to obtain multiple exposures in the [O III]/2 and the off-emission
 MB#571/25_ESO863 filters sufficient to cover the gaps between the WFI chips and
 the whole 
area of the galaxy by four pointings, displaced from the centre but overlapping.
 The 
overlap ensures high signal in the more crowded central regions. The [O III] line
 is 
the brightest in a PN but this line is also emitted by HII regions. The same coverage
 
as at [O III] at H-alpha (and off-H-alpha using the MB#696/20_ESO869 filter), allows
 PN to be found by their [O III]/H-alpha ratio. Since there are already WFI H-alpha
 images of this galaxy this is put at 2nd priority. But the spatial coverage of the
 previous imaging at H-alpha is less than required for this survey, so the priority
 of the H-alpha imaging is still high. The set of OB's for each field 1-4 (named
 NGC300_f1 to NGC300_f4)
are identical. They contain a total of 5 exposures for each filter
(except for [OIII] which has 8 exposures) at different dither positions
in order to cover the inter-chip gaps. 
OBs for each field consist of:
4 OIII/2 (O3) OB's:
  - each with two offset exposures
3 MB#571/25_ESO863 off-band (b) OB's:
  - 2 of which have 2 exposures and the third 1 exposure
2 H-alpha/7 (HA) OB's:
  - 1 with 2 and other with 3 dithered exposures
2 MB#696/20_ESO869 off-band (r) OB's:
  - 1 with 2 and other with 3 dithered exposures
  
In addition, for the field 1 (only) there is one OB with short exposures 
for all four filters OIII/2 (O3), off-band 571/25 (b), H-alpha/7 (HA) and 
off-band 696/20 (r), each with 1 exposure) which is to be executed under 
photometric conditions. They are going to be used to tie in the photometric 
zero-points for all the other OBs. This OB is labeled with PHOT_ prefix.

List of OB's for NGC 300
------------------------
NGC 300 field 1 photometric OB  | filter names:
PHOT_N300.obx  | NB#OIII/2 filter, MB#571/25_ESO863 filter, NB#Halpha/7_ESO856 filter
                 and MB#696/20_ESO869 filter

NGC 300 field 1 [OIII]/2 filter | number of offsets:
N300f1_12_O3.obx | 2 offsets 
N300f1_34_O3.obx | 2 offsets
N300f1_56_O3.obx | 2 offsets
N300f1_78_O3.obx | 2 offsets

NGC 300 field 1 off-band MB#571/25_ESO863
N300f1_12_b.obx  | 2 offsets
N300f1_34_b.obx  | 2 offsets
N300f1_5_b.obx   | 1 offset

NGC 300 field 1 H-alpha/7
N300f1_12HA.obx  | 2 offsets 
N300f1_345HA.obx | 3 offsets

NGC 300 field 1 off-band MB#696/20_ESO869
N300f1_12r.obx   | 2 offsets
N300f1_345r.obx  | 3 offsets

Same pattern of OB's for fields 2, 3 and 4 (N300f2, N300f3 and N300f4).

Waiver Requests

```
No Waiver Request was submitted
```

Critical Observing Condition Constraints

```
None
```

Time-Critical Aspects

```
None
```

Special Execution Requirements

Since the [O III] and off band imaging (OB's b), and similarly the H-alpha
 
and off band (medium r band), must be subtracted to reveal the PN, the on-band
+ off-band images can be viewed as related OB's in the sense that the conditions
 should 
be as close as possible for both.

Special Calibration Information

Calibration OBs for these narrow-band imaging OBs consist of observations
 of
1 standard Landolt field (Mark A) and 1 spectrophotometric standard
(LTT377) and dome and sky flat field OBs.
Standard star field
STD_MarkA_al.obx

The standard field OB with four filters should be executed at least once and 
with the spectrophotometric standard and the PHOT_N300 OB.  

LTT377 Spectrophotometric standard star
(V = 11.23, B-V = +0.48, Spectral type: F) 
LTT377_filts.obx
The spectrophotometric standard OB should be executed close to the PHOT_N300 OB.

Dome flats for the four filters
DF_571b.obx
DF_696r.obx
DF_HA.obx
DF_O3.obx

Sky flats for the four filters
SkyF_571b.obx
SkyF_696r.obx
SkyF_HA.obx
SkyF_O3.obx

ToO Information

```
None
```

ToO Activators List

```
N/A
```

Is this a Pre-imaging run ?

```
false
```

Pre-imaging Requirements

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None
```

Source(s) of Pre-imaging

---(Empty)---

Pre-imaging sources not listed above

---(Empty)---

Do all your OBs comply with the instrument-specific requirements listed on the instrument-specific Phase 2 web page ?

If this is a pre-imaging run, did you select PRE-IMAGING for the Observing Category for each Observing Template ?

```
N/A
```

Do all your finding charts comply with both the general and instrument-specific Phase 2 Web Pages ?

If you submitted OBs for standard stars, did you specify the magnitude and spectral type of all standard stars in the OBs ?

Have you included OBs for any calibrations that you need but which are not part of the Calibration Plan ?

If you are observing Moving Targets, have you attached suitable ephemeris files to your OBs?

```
N/A
```

If you have preferences which OBs should be executed first, did you make use of the User Priority field in the OBs ?

If this is a run that requires coordinated observations with other facilities, did you give proper instructions in the Time-Critical Aspects Section ?

```
N/A
```

Did you set 'New Preset' flag in all acquisition templates to 'True'?

```
N/A
```

Have all your submitted OBs the same filter for the acquisition template and for the first science template?

Did you combine calibration templates with science templates for any OB?

Did you combine imaging and spectroscopic templates for any OB?

Did you submit any Focus template?

Last creation of page: Tue Oct 6 15:40:08 2009
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