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CTIO Home > SMARTS Consortium > Telescopes, Instruments & Schedules > SMARTS 0.9-m Telescope > 0.9-m Observing Mode

0.9-m Observing Mode

0.9m Observers in SERVICE MODE

  • Welcome and Overview [1] --- READ THIS FIRST
  • What Observers Need To Do [2] --- SERVICE OBSERVING
  • Example Observing Template [3]
  • Template Tips (~ FAQs) [4]
  • Overhead Times for Observing [5]

0.9m Observers in USER MODE

  • What Observers Need To Do [6] --- USER OBSERVING
  • Observing Hints for the 0.9m [7]

0.9-m Welcome & Overview

    Contents
  1. Contact People
  2. Scheduling
  3. Instrumentation
  4. Known issues at the 0.9-m
  5. Planning Observations
  6. What you need to do now

Hello, SMARTS, Chilean, and NOAO users!                

If you have recently been awarded time on the 0.9-m, you will soon be contacted by 0.9-m coordinator Adric Riedel with detailed instructions on how to proceed.  Here, we describe the preparation process (in fact, is almost verbatim from the e-mail you will receive) to ensure you obtain the best possible data for your project.  If you are preparing a proposal for the 0.9-m, this website provides information that will best inform you of the capabilities and limitations of the two observing modes (user and service).  In either case, this website will hopefully help with your preparations. 



C O N T A C T   P E O P L E
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The responsible authorities for the SMARTS 0.9m are:

riedelatchara [dot] gsu [dot] edu (subject: SMARTS%200.9m%20Correspondence) (Mr. Adric Riedel) (GSU), SMARTS Fellow for the 0.9m.

thenryatchara [dot] gsu [dot] edu (subject: SMARTS%200.9m%20Correspondence) (Dr. Todd Henry) (GSU), SMARTS 0.9m Coordinator.
jsubasavageatctio [dot] noao [dot] edu?subject=SMARTS%20General%20Correspondence">
Dr. John Subasavage
[8] (CTIO), SMARTS Telescope Fellow at CTIO

charles [dot] bailynatyale [dot] edu (subject: SMARTS%20General%20Correspondence) (Dr. Charles Bailyn) (Yale), Director of the SMARTS Consortium.
    

Questions about 0.9m operations should be directed to Mr. Riedel and Dr. Henry; GSU has been using the 0.9m since 1999 and has been coordinating the 0.9m since the beginning of SMARTS in 2003.

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S C H E D U L I N G
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Time on the SMARTS 0.9m is a mix of classical observing and service observing, divided into (generally) alternating seven night blocks the CTIO staff call 'turnos'.  Within each 'turno', time is assigned by the night (or half-night, but not less).  As such, we cannot guarantee weather conditions.

The observing schedule for the 0.9-m is posted (and updated) here [9]:

Under the 'TIMES' link for your night, you will also find a listing of precisely what hours you have been given. This will aid in planning your programs.

Unless you wish to keep your program completely confidential, this is also where it will be posted for the service observers to see.

Three weeks before your scheduled observations' turno, you will be contacted by Adric Riedel, who will send you a template to use to plan your program.  Reminders will be sent two weeks before, and 10 days before, as needed.  IF YOU DO NOT RESPOND WITH AN OBSERVING LIST BY 7 DAYS BEFORE YOUR TURNO BEGINS, YOU WILL FORFEIT YOUR TIME.

You will also need to fill out the instrument form at

      http://www.ctio.noao.edu/forms/supportforms/ccd_direct.php [10]

(using 0.9M+Tek 2048 CCD) to confirm your time and request the filters you will need.  This is critical for the 0.9m in order to be sure that your desired filters are available.

After your observations are complete, Mr. Riedel will contact you again with the night reports from your scheduled nights and instructions on how to download the data from GSU's FTP server.  Data will be held there for 30 days as bzip2-compressed fits files plus a text file with brief header information.

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I N S T R U M E N T A T I O N
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Pictures of the instrument can be found here [11]

The SMARTS 0.9m is a 36-inch (91-cm) Boller & Chivens telescope, built in 1965 and currently operated by the SMARTS Consortium for NOAO.

The only available instrument on the 0.9m is a Tektronix 2048x2046 CCD with 65K pixel depth and a FOV of 13.69' on the sky, with a pixel scale of 0.401"/pix (not 0.396"/pix as listed on the CTIO page below). This arrangement has lasted for more than 10 years, and has been incredibly stable, both photometrically and astrometrically.

More detailed information about the following points may be found here [12]:

The Tektronix CCD can be run in a number of modes:

      FULL chip (13.6'), ONE amp readout    (3 min readout)
      FULL chip (13.6'), QUAD amp readout   (0.8 min readout)
      Central QUARter (6.8'), ONE amp readout  (0.8 min readout)
      Central QUARter (6.8'), QUAD amp readout  (0.3 min readout)

Quad-readout frames will need to be processed with a tool like IRAF's quadproc, as each of the amplifiers has its own bias level.  In single-amp mode, the lower left (ll) amplifier is usually used.

There are also three available gain settings:

      1: (unavailable, failed in March 2009)
      2: Read Noise ~ 1.6 ADU = 3.9 e-
      3: Read Noise ~ 1.8 ADU = 3.2 e-
      4: Read Noise ~ 2.6 ADU = 2.7 e-

Finally, the 0.9m accepts two filter wheels. There are two sizes available, 8-slot wheels for 3"x3" filters, and 5-slot wheels for 4"x4" filters.

CTIO has a large assortment of filters available for use, listed here [13] (many linked to their filter traces):

CTIO also has some old 2"x2" filters useable in the 0.9m, listed here:

      http://www.ctio.noao.edu/instruments/filters/index.html [14]

Their use is not recommended --- many of them are seriously degraded and all of them vignette on the 0.9m in FULL chip mode.

Please make your filter request as specific as possible when you fill out the instrument form.  These filters are shared between telescopes so CTIO staff will need time to make sure the right ones are available for the 0.9m on your nights.

      http://www.ctio.noao.edu/forms/supportforms/ccd_direct.php [10]

The most common filters in use at the 0.9m are:

* The Tektronix UBVRI 3"x3" filter set (roughly Johnson/Kron-Cousins), which is almost always comprised of the Tek #2 UBRI filters and the Tek #1 V filter.  Filter traces for all three Tek filter sets are available at
      http://www.chara.gsu.edu/~thenry/SMARTS/smarts.0.9m.filters.pdf [15]

* An SDSS ugriz 4"x4" filter set (Sloan filters, not to be confused with our Thuan-Gunn griz set) Details about the common filters (e.g. exposure time estimates) are available here:

      http://www.chara.gsu.edu/~thenry/SMARTS/smarts.0.9m.filters.text [16]

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K N O W N   I S S U E S   A T   T H E   0 . 9 M
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HEADERS --- there is a known issue with the headers.  The "new" TCS installed in 2005 does not properly communicate with the ARCON data acquisition computer, and as such several header keywords have meaningless values.  We are continuing to work on this long-term problem, but do not yet have a solution.  For details, see

      http://www.chara.gsu.edu/~thenry/SMARTS/smarts.0.9m.tcs [17]

PHANTOM OF THE 0.9M --- occasionally, the dome will spin 360 degrees seemingly without cause.  Many tests have been done to determine the cause, and no convincing gotcha has been found.

POINTING --- pointing is typically good to 20 arcseconds, which means it is reliable enough that you should be able to use the J2000 coordinates of your intended field.  However, we HIGHLY recommend that you provide an electronic finder (with orientation and scale labels!)
on a working website for every target.

BAD COLUMNS --- Like many CCDS, the Tek 2k CCD on the 0.9m has bad columns.  These can be avoided.  Otherwise, a bad pixel mask [18] (unbinned - simply rename to exclude '.txt') can be used to interpolate across the columns.

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P L A N N I N G   O B S E R V A T I O N S
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A sample observation list template (ASCII format) can be found here [3].  YOU MUST USE THE TEMPLATE FOR YOUR OBSERVATIONS.  You will be contacted by the 0.9m coordinator with a template appropriate for the current observing semester.  The closer you adhere to the format, the smoother your observations will go.

A few tips and requests, because we at the 0.9m like to under-promise and over-deliver:

* No non-sidereal programs in service mode.  The timing and instrument changes make this better suited to user mode.

* No polarimetry programs in service mode.  As this is a non-standard instrument setup for the 0.9m, it is better handled as user time.

* Assume you are proposing for automated observing.  None of us are familiar with your program, so everything you need must be spelled out.

* You may only have TWO possible programs (photometric, nonphotometric backup) per night, and each must be entirely self-contained.  A single program that can be done in either case (ignoring standard star observations if non-photometric, for example) is also fine.

* Assume your program will be set in stone once started.  We do not have the facility to change target lists for night #2 based on what was observed on night #1.

* Assume the observer is going to go straight down your list as the night progresses.  Use the priority system to make sure the observer knows which targets can be skipped if time is short.

* For best results when requesting absolute photometry, use an airmass calculator (such as

      http://www.briancasey.org/artifacts/astro/airmass.cgi [19])

to determine the exact times (UT) you want your standards observed, and list each visit as a separate observation.

* The weather at CTIO is worst in winter.  Programs scheduled for December or January (Chilean summer) can likely expect to get more than 70% photometric nights, but the odds of photometric weather in August are low.

* Plan for overhead, as detailed for service mode at:
      http://www.chara.gsu.edu/~thenry/SMARTS/smarts.overheads [20]

* Keep it simple.  Our observers are Chilean CTIO employees.  They are not scientists, nor is English their first language, and Mr. Riedel does not want to reword parts of your program to make it clearer for them.

The following requests work well:

* integrating for a certain amount of time

* integrating to X number of peak counts on a target object (marked on a finder)

* dithering between observations (this goes for sky flats as well)

* moving the target off the center of a quad-readout frame

* explicit timing of observations (put UT times in the notes)

* listing objects, such as standard stars, multiple times if you want them observed at different airmasses

* "use ND filter if (object) saturates in less than X seconds"

* "observations may begin in twilight"

* observing a target continuously for an entire night/ until UT time X

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W H A T   Y O U   N E E D   T O   D O   N O W
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Anticipate an email from Mr. Riedel, perhaps begin compiling the necessary information as outlined in this page, and promptly respond with the requested information.  You will then be placed on the "confirmed" list for observations in the upcoming semester.

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If there are any further questions about anything in this email, feel free to contact Mr. Riedel or Dr. Henry.

Clear Skies,

Adric Riedel
SMARTS Fellow
Graduate Student, Georgia State University

Dr. Todd J. Henry
Director, RECONS
Professor of Astronomy, Georgia State University

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0.9-m Duties for Service PIs

What observers with service time need to do --- short list of highlights

The following is a checklist for you to work through in order to have your service observations made successfully.


Observing Template

You must have your observing templates sent to riedelatchara [dot] gsu [dot] edu (subject: SMARTS%200.9m%20Correspondence) (Adric Riedel), GSU SMARTS Fellow, 7 days before your turno stars, OR YOUR TIME WILL BE FORFEITED --- NO EXCEPTIONS.

Notifications and example templates will be sent to you on the following schedule:

21 days before your turno starts --- INITIAL CONTACT

14 days before your turno starts --- REMINDER 1

10 days before your turno starts --- REMINDER 2

7 days before your turno starts --- *** HARD DEADLINE ***


CTIO Instrument Form

You must fill out a CTIO instrument form at

http://www.ctio.noao.edu/forms/supportforms/visitor_support.html [21]

You should send this in at least TWO WEEKS before the first night of your turno.  This allows us to catch any problems, such as whether or not your requested filters are scheduled for a user at another telescope.


Getting your data

For data acquired via service mode, the GSU 0.9m SMARTS Fellow (as of JUL 2009, Adric Riedel) will ftp the data back to a staging area at GSU.  You will be given instructions on how to retrieve your data shortly after the observations are taken.

YOU WILL HAVE 30 DAYS TO RETRIEVE YOUR DATA, IF YOU WAIT LONGER THAN THAT, YOU DO SO AT YOUR OWN PERIL


Important Notes

  1. Non-sidereal tracking programs WILL NOT BE SUPPORTED via service time at the 0.9m.  They can be proposed and carried out via user time if you desire.
  2. Polarimetry observations WILL NOT BE SUPPORTED via service time at the 0.9m.  They can be proposed and carried out via user time if you desire.

0.9-m Template Tips

Top 10 Tips for Preparing Your Template for 0.9-m Service Observing

********** WARNING **********

PREPARING YOUR TEMPLATE TAKES FAR MORE WORK THAN YOU PROBABLY ANTICIPATE, SO START EARLY!
 

  1. The form must be returned in ASCII format.
  2. Tell us whether you will be using the FULL chip (13.6 arcmin) or QUARTER chip (6.8 arcmin) mode, and what gain you wish to use.
  3. Be sure to include a list of filters will you need.
  4. Clearly state what calibration frames you need.
  5. Explicitly say if you need photometric conditions, or if non-photometric conditions are fine.  If two programs are submitted (i.e., photometric and non-photometric), clearly designate the two and make them able to "stand alone".  YOU CAN ONLY GIVE TWO OBSERVING OPTIONS FOR A NIGHT, NO MORE.  The observer can use the photometric list if the weather is photometric and completely disregard the non-photometric program that night.  If a particular target should be observed under either condition, it should be included in both lists.
  6. If a program is submitted that requires a given target to be observed more than once per night (e.g., a standard star at different airmasses), structure the observing list in a time-sequential order and list that object multiple times.  This prevents missing observations of standards at necessary airmasses.
  7. Make a reasonable assessment of what you can accomplish in the time awarded.  See www.chara.gsu.edu/~thenry/SMARTS/smarts.overheads [20] for a listing of true overheads.  There is an exposure calculator for this telescope/CCD combination in IRAF.  Also, there is a new calculator [22] using data taken in 2011 and is the preferred one to use.
  8. If you require that exposure times be adjusted based on the observing conditions, provide a finder with a clearly marked target and state an acceptable range in peak counts for that target (a fair limit is 50,000 counts, to avoid saturation at 64,000 and to leave a bit of breathing room).  For example, if you are doing precision astrometry and require at least 30,000 counts on a target, you could set an acceptable range of 30,000-40,000 counts and the observer will adjust the exposure time to meet that requirement.
  9. Finders are HIGHLY RECOMMENDED for all targets.  The 0.9m typically points to 30 arcsec.  Finders should be POSTED ON THE WEB AT A RELIABLE website so they can be quickly checked by the observer.  Each finder chart must have:
  • coordinates
  • N/E directions
  • scale (i.e. 10 arcmin on a side)
  • target marked
Note: if the observer must use the paper copy of Landolt standards, he must flip through several pages to locate the correct finder, which takes time.  Googling Landolt standards will routinely yield the latest website giving finder charts (the website sometimes moves, so we don't list it here).
  1. Double-check all coordinates.  Seriously.

Once your observing template has been examined (and likely revised) by the GSU SMARTS Team, you can check it on the nightly schedule website at:

        http://www.chara.gsu.edu/~thenry/SMARTS/scheduleYYYYA.htm [23], or
        http://www.chara.gsu.edu/~thenry/SMARTS/scheduleYYYYB.htm [24]

 

0.9-m Overhead Times

Timing Overhead for Various Actions at the 0.9-m

There are two sets of times listed below, LIGHTNING and HUMAN.  The LIGHTNING case assumes that everything goes absolutely perfectly, with observer reaction time an absolute minimum.  This does not occur in real life.  The HUMAN overhead is the one that should be adopted for all service observing programs.

  LIGHTNING HUMAN
Slew/Target Acquisition 3 min 5 min (variable)
Change Directory/File Name 1 min 1 min
Change Chip Setup 1 min 2 min
Change Tracking (non-sidereal) 1 min 2 min
Focus Frame 3 min 6 min
Chip Readout    
  Full Chip/Four Amps 0.8 min 0.8 min
  Full Chip/One Amp 3 min 3 min
  Quarter Chip/Four Amps 0.3 min 0.3 min
  Quarter Chip/One Amp 0.8 min 0.8 min


Example

You have a short service program that is inserted into a longer program scheduled for the same night.  You want to use a different chip setup, non-sidereal tracking, and a single 300 second integration.  The required time is:
 

Slew/Target Acqusition 5 min
Change Directory/File Name 1 min
Change Chip Setup 2 min
Change Tracking (non-sidereal) 2 min
Focus Frame 6 min
Chip Readout = Full Chip/Four Amps 0.8 min
Integration Time 5 min
   
Change Directory/File Name BACK 1 min
Change Chip Setup BACK 2 min
Change Tracking (non-sidereal) BACK 0 min (flip switch)
   
Total Time for Observation 24.8 min

0.9-m Duties for Classical PIs

What Observers with User Time Need to do Before Going to Chile

This document outlines the duties of proposers who have user time on
the CTIO 0.9m.  This includes both NOAO and SMARTS users who are going
to CTIO to take their own observations.  It is the observer's
responsibility to carefully consider all relevant information at the
Georgia State University (GSU) SMARTS website at

http://www.chara.gsu.edu/~thenry/SMARTS [25]


1. Basic Information

For us to understand what observing modes are most popular on the 0.9m, you may be contacted by members of the GSU SMARTS team to find out the following information:

  1. Have you been awarded your observing time via the SMARTS Consortium, NOAO or Chilean Telescope Allocation Committee (TAC)?
  2. Who will be at the telescope?
  3. Will you be using the FULL chip (13.6 arcmin) or QUARTER chip (6.8 arcmin) mode?
  4. What filters will you need for your observations?


2. Travel Information

General travel information can be found at the fundamental site

http://www.ctio.noao.edu/diroff/obser_trav.htm [26]

If someone from your team will be traveling to CTIO, fill out the travel form for CTIO at

http://www.ctio.noao.edu/travel/itinerary.php [27] (or, http://www.ctio.noao.edu/forms/ [28] and click on Travel Plans)

In the "Proposal Number" please write SMARTS.

You can arrange to be met at the La Serena airport by a cab that will take you directly to the AURA offices (and your dorm).  If you arrive on time, you should be met after claiming your bags.  Otherwise, you may need to catch your own taxi from the airport to AURA/CTIO in "Colino el Pino".  You will need to pay in pesos, so make sure you have some.  To return to the airport after your run, ask the folks in Reception to arrange for a taxi from the La Serena motel, or just go directly to the airport from the mountain --- ask the carryall driver to drop you off at the airport.

Pay your bill at the ROB (Round Office Building) on the mountain.  Credit cards are preferred (but note that many credit cards charge an extra handling fee for foreign charges.)

*** If in dire need of travel assistance only, as a last resort contact xherrerosatctio [dot] noao [dot] edu (subject: Observer%20Travel%20Assistance) (Ximena Herreros).


3. Instrument Setup Form

You must fill out an instrument form at

        http://www.ctio.noao.edu/forms/supportforms/visitor_support.html [21]

You should send this in at least TWO WEEKS before the first night of your observing run.  This allows us to catch any problems, such as whether or not your requested filters are scheduled for a user at another telescope.


4. Learning about the 0.9-m

You should familiarize yourself with operations at the 0.9m.  The link entitled "Observing Hints for the 0.9m" will give you some information about how to use the 0.9m.  This link is the one just below the link that got you to the page you are reading now.  It can also be found at:

http://www.chara.gsu.edu/~thenry/SMARTS/smarts.observing.YYYY.MMDD [29]
 


Source URL (retrieved on 02/09/2013 - 00:35): http://www.ctio.noao.edu/noao/content/09-m-Observing-Mode

Links:
[1] http://www.ctio.noao.edu/noao/content/09-m-Welcome-Overview
[2] http://www.ctio.noao.edu/noao/content/09-m-Duties-Service-PIs
[3] http://www.chara.gsu.edu/~thenry/SMARTS/smarts.template
[4] http://www.ctio.noao.edu/noao/content/09-m-Template-Tips
[5] http://www.ctio.noao.edu/noao/content/09-m-Overhead-Times
[6] http://www.ctio.noao.edu/noao/content/09-m-Duties-Classical-PIs
[7] http://www.chara.gsu.edu/~thenry/SMARTS/smarts.observing.2010.0312
[8] mailto:<span class=
[9] http://www.chara.gsu.edu/~thenry/SMARTS/
[10] http://www.ctio.noao.edu/forms/supportforms/ccd_direct.php
[11] http://www.ctio.noao.edu/noao/content/09-m-History
[12] http://www.ctio.noao.edu/noao/content/Tek2K
[13] http://www.ctio.noao.edu/noao/content/CTIO-3x3-inch-and-4x4-inch-Filters
[14] http://www.ctio.noao.edu/instruments/filters/index.html
[15] http://www.chara.gsu.edu/~thenry/SMARTS/smarts.0.9m.filters.pdf
[16] http://www.chara.gsu.edu/~thenry/SMARTS/smarts.0.9m.filters.text
[17] http://www.chara.gsu.edu/~thenry/SMARTS/smarts.0.9m.tcs
[18] http://www.ctio.noao.edu/noao/sites/default/files/telescopes/smarts/tele09/badpix.pl.txt
[19] http://www.briancasey.org/artifacts/astro/airmass.cgi
[20] http://www.chara.gsu.edu/~thenry/SMARTS/smarts.overheads
[21] http://www.ctio.noao.edu/forms/supportforms/visitor_support.html
[22] http://www.ctio.noao.edu/noao/content/SMARTS-Imager-Exposure-Calculator
[23] http://www.chara.gsu.edu/~thenry/SMARTS/scheduleYYYYA.htm
[24] http://www.chara.gsu.edu/~thenry/SMARTS/scheduleYYYYB.htm
[25] http://www.chara.gsu.edu/~thenry/SMARTS
[26] http://www.ctio.noao.edu/diroff/obser_trav.htm
[27] http://www.ctio.noao.edu/travel/itinerary.php
[28] http://www.ctio.noao.edu/forms/
[29] http://www.chara.gsu.edu/~thenry/SMARTS/smarts.observing.YYYY.MMDD