README web version of /home/usg/OPS/MTS/readme_xml/readme_82501900

Principal Investigator Email Address

```
ngibson07@qub.ac.uk
```

Estimated Total Execution Time (hours, including overheads)

```
4.5
```

General Description

This OB will be used to observe WASP-19 during a secondary transit of
 the system, i.e. when the planet passes behind it's host star. This is expected
 to produce a dip in the light curve of about 0.1% - 0.3% in flux and thus requires
 extremely high precision photometry from the ground. We will observe the target
 for ~4.5 hours so that we have excellent coverage both before and after the transit
 in order to properly normalise the curve and evaluate the systematics. In terms
 of photons statistics this should easily be possible from the ground, but the challenge
 in observations of this type is to minimise the systematics.

These observations are of course time critical, as the OB must coincide with the
 secondary transit of WASP-19. Details are in the "Time-Critical Aspects" part of
 this README.

Target acquisition will be done with the HAWKI_img_acq_MoveToPixel template for
 very precise pointing, so that the field can be checked prior to the science template
 being executed. This is to ensure that the target and comparison stars (marked with
 a circle in the charts along with K mag) are >~20 arcsecs from the edge of the
 chips, so they don't fall on the edges during the jitter pattern, and also so that
 some brighter stars (also marked) are not included in the field. A NIR DSS image
 is attached showing the expected field of view of HAWK-I (Field Centre: RA 09:53:57
 DEC -45:38:54).

The science images will be taken using the HAWKI_img_obs_AutoJitter template in
 the NB2090 filter. An exposure time of 10s will be used and 6 images will be taken
 at each offset position as we cannot move the telescope more than once per minute.
 The observations will then consist of 205 random offsets in a 35 arssec box with
 1 minute of integration time at each, resulting in 1230 x 10s images over a ~4.5
 hour period.

The observations were planned assuming a seeing of 0.8 arcsec, requiring that the
 brightest star in the field (K ~ 9.5) does not exceed the linearity limit of the
 chip. If the seeing is better than 0.8 arcsec during the observations, we request
 that badAO be used in order to defocus the PSF to a FWHM of ~1.0 arcsec.

Waiver Requests

Waiver ID: 282.C-5019A.01

As our observations require coverage of a secondary transit ~4.5 hours needs to
 be spent continuously observing the same target. This is to ensure not only the
 full transit is sampled but also that sufficient out-of-transit data is available
 to normalise the lightcurve and to properly characterise the systematics. This was
 justified in our phase 1 proposal.

A waiver was therefore submitted to ESO on 26th Nov via email to request permission
 to submit OBs that take longer than 1 hour to complete. This was granted with waiver
 ID 282.C-5019A.01 on the 30th Nov.

Critical Observing Condition Constraints

We expect the observations to be limited by systematics in the instrument,
 therefore we didn't request a photometric night as our minimum conditions. We would
 of course prefer a clear night but will specify it as thin cirrus as specified in
 the phase 1 proposal which may still provide useful results using relative photometry.
 As we would like to defocus the telescope anyway, seeing is not important to us
 and no seeing constraints are applied. The moon and airmass have already been checked
 for each of the time constraints given and so no constraints are applied for them
 either.

Time-Critical Aspects

These observations must coincide with the secondary transit, and therefore
 the observing blocks must be executed within one of the following time windows.
 These are (as provided in the OB):

[2009-01-26T04:00:00] - [2009-01-26T08:30:00]
[2009-02-10T03:45:00] - [2009-02-10T08:15:00]
[2009-02-18T01:00:00] - [2009-02-18T05:30:00]
[2009-02-25T03:15:00] - [2009-02-25T07:45:00]
[2009-03-31T01:30:00] - [2009-03-31T06:00:00]

Due to adverse weather affecting the first 4 observing windows, a further 9 time
 windows are provided below for our observations:

[2009-03-12T03:00:00] - [2009-03-12T07:30:00]
[2009-03-16T01:50:00] - [2009-03-16T06:20:00]
[2009-03-20T00:30:00] - [2009-03-20T05:00:00]
[2009-03-27T02:40:00] - [2009-03-27T07:10:00]
[2009-04-04T00:00:00] - [2009-04-04T04:30:00]
[2009-04-15T01:00:00] - [2009-04-15T05:30:00]
[2009-04-18T23:50:00] - [2009-04-19T04:20:00]
[2009-04-30T00:30:00] - [2009-04-30T05:00:00]
[2009-05-03T23:40:00] - [2009-05-04T04:10:00]

Special Execution Requirements

---(Empty)---

Special Calibration Information

Extra calibrations were requested at phase 1 which accounted for 1/2 hour
 of the total 5 hours awarded to this proposal. Apart from a standard sequence of
 twilight flats in the NB2090 filter, if operationally possible we request observations
 of a second sequence of flats in one of the following few nights. These would prove
 very useful for our programme. We also request 40 extra darks of 10s exposure time
 as the standard calibrations of 10 exposures / DIT-NDIT are not sufficient for our
 needs. These extra calibrations are required for ultra precise photometry, so that
 no significant extra noise is added at the reduction stages.

ToO Information

---(Empty)---

ToO Activators List

---(Empty)---

Is this a Pre-imaging run ?

```
false
```

Pre-imaging Requirements

---(Empty)---

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 ?

```
N/A
```

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

```
N/A
```

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 ?

```
N/A
```

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
```

If you submitted OBs for standard stars, did you use the provided StandardStar templates ?

```
N/A
```

If you are using a specific offset pattern or position angle, did you check carefully the definition in the manual ?

```
N/A
```

Did you enter the magnitude of the brightest star in the field-of-view in the 'Instrument Comments' field of each OB ?

If you use the MoveToPixel acquisition, have you given clear instructions on the FC and in the OB comment section as to how the field should be centered ?

Last creation of page: Tue Oct 6 15:40:28 2009
If you have comments, please contact usd-help@eso.org