1st Quarter 2007 Proposal Deadlines, Mimir Status

1st Quarter [Jan, Feb, Mar 2007] Observing Proposals are Due On:

• November 1 for outside visitors requesting non-collaborative time - these proposals must use the combined visitor TAC proposal submission path

• October TBD for BU/IAR internal proposals

• Lowell Observatory internal proposals - contact Bob Millis, Director, Lowell Observatory

Outside Visitor Time

This is time set aside for outside scientists to use Mimir and/or other instruments on the Perkins telescope. Operators are *not* provided. Outside users must become certified prior to conducting solo observations. Additionally, for Mimir, certified users may *not* certify new users, which is different than for other instruments on the Perkins.

Scientists considering proposing Outside Visitor time with Mimir are *strongly* encouraged to contact Dan Clemens and/or Marc Buie well in advance of the proposal due date.

Notes on User Certification

Solo use of Mimir requires that the observer be certified for Mimir use. This involves spending several nights at the Perkins telescope using Mimir with Marc Buie (Lowell Observatory), Dan Clemens (Boston University), or Brian Taylor (Boston University) who are at present the only Mimir certifiers.

Outside visitors proposing Mimir use *must* contact one of the certifiers prior to submitting their proposal(s) to arrange a plan for certification. This plan must be included in the submitted proposal. Note that polarimetry certification is best done with Dan Clemens and spectroscopy with Marc Buie.

Notes on Commissioned Observing Modes for Mimir

At this time, the camera block appears to be moving and functioning normally, allowing users access to both F/17 and F/5 plate scales. Also, the 2005 Nov/Dec detector tuning run resulted in a much better set of operating conditions for the detector array. Well depths are now about 7,500 ADUs (60,000 electrons) and dark current/hot pixels are much reduced.

The following observing modes are commissioned for use. Modes not listed below are *not* commissioned for use.

1. Imaging (both F/5 and F/17)
   1. Broadband imaging in J, H, Ks
   2. Narrowband imaging with H2On, H2Off
   3. Broadband imaging in L (F17 only, generally using sub-frame readout)
   4. Broadband imaging in M (F/17) has not been tested, but assumed commissioned
2. Imaging Polarimetry in the H-band
   1. F/5 works
   2. F/17 should work, not tested but assumed commissioned
3. Spectroscopy (JHK, LM, SED grisms)
   1. F/5 from 1-2.5 microns
   2. F/17 from 1-5.5 microns

Array operating modes available for general use are:

Full-Frame Readout - in CDS or non-CDS modes

Sub-Frame Readout - which allows reading a rectangular shaped region, currently centered on the array center. This mode should be used for L-band direct imaging and spectroscopy, where faster read times are necessary to prevent filling detector electron wells.

Fowler-type sampling - this mode obtains up to 16 readouts of the array at the beginning and end of each integration. The images generated can be averaged to effect a reduction in read noise. Since each read takes about 0.25 sec, this mode is most useful for JHK spectroscopy and narrow band (H2 S1 line) imaging, where the integration times are long and read noise may dominate the total noise budget.

Array Bias Options - these were established in late 2005:

Normal Bias (photoconductor reverse biased to -0.875 V) - produces the best cosmetics, least dark current, but only about 1/2 of the well depth of the highest bias levels (that is, about 60,000-90,000 electrons instead of twice those values).

High Bias (reverse bias of -1.35V) - produces the deepest wells (up to 160,000 electrons per pixel), but at the expense of lots of hot pixels and high dark current. May be of use for very short L & M band imaging and spectroscopy.

Mimir servicing schedule:

We plan to conduct extensive Mimir servicing in mid-late December 2006. This servicing will be devoted to upgrading the slit/decker unit for higher reliability and repeatability of slit positioning, reducing filter wheel binding, and perhaps addition of some new filters.