# Presentation: 093366

## SEGUE  Meeting

- AM Talks
- towards a task list:
- pipeline changes/updates
- Target Selection updates

- SDSS Collaboration Meeting Oct 2, 2004
- Pittsburgh

## Reminder: Key project SEGUE science drivers:

- 1. Map Halo structure – trace streams such
- as the Sagittarius and  Monoceros--
- Canis Major streams around the Galaxy.
- Constrain Dark Matter potential/shape.
- 2. Disk(s) Structure – Study the thin/thick disk
- transition, and the transition to the
- halo/spheroid in number counts (model
- parameters scale lengths, falloffs w/ radius,
- metalicities, kinematics and formation history.

-         Over-arching Question:
-         Can the SEGUE imaging and spectroscopy meet the basic
-         science goals, as laid out in the SEGUE white paper and
-         various SEGUE proposals?

## Fibers per plate Pair:

- WD         25
- CWD       10
- BHB     125
- F TO     150
- G          375
- K III     125
- Low Fe150
- K V      125
- Ms         50
- AGB       10
- SKY        96
- QA           15
- RED/SP    16

## Saturday Oct 2, 2004 AM  (Room:  Allen 318) 

- 9:00 Intro
- 9:10 J. Bochanski    SDSSWhite Dwarf/M-Dwarf pairs, red Star update
- 9:30 J. A. Smith       Photometry Update, WD/MD stars
- 9:45 C. Rockosi       Radial Velocities for SEGUE
- 10:15-10:45 Break
- 10:45  C. Allende-P. Metalicity, Gravity determination
- 11:15  R. Wilhelm      Metalicity, Gravity determination – hot stars
- 11:45  T. Beers          Atmospheric Parameter determination in stars
- 12:30-1:30 Lunch
- 1:30-3:30  Open discussion spectroscopic pipeline, SEGUE science
- 4:00-5:30  SEGUE target selection category by category

## Observing strategy:

- Imaging: 3900 sq deg, mostly at low |b|
- Spectra: 240,000 stellar spectra (520 plate-equivalents)
- of stars of a range of colors.

## Strip 1100S  (l=50 deg)  CMDs (g-r,g)

- -44                 -41                -38                  -35
- -32                 -29                -26                 -23
- -20                 -17                -14                  -11

## SEGUE Level  0 Deliverables:

- Medium latitude frames (|b| > 10 deg) processed through PHOTO, initial calibration with PT patches to roughly
- SDSS-I accuracy (i.e.  g-r errors of 2%). Flat file format ok
- (tsObj catalogs). [turn around in time for Target Selection: one
- month or one year time scales, can use SDSS-I imaging]
- Target Selection Pipeline for SEGUE TS, with documentation, including usual TS items: skies, guide stars, redden standards,
- plPlugMapT input files.
- Spectro plates processed through existing SDSS-I 2D+1D pipelines with improved Radial Velocities from  ELODIE template fits (or equivalent) for all stars with S/N>~5.
- First-pass estimation of stellar atmos params:
- Teff, [Fe/H], log g for stars with g < ~18.5. 'Value added Catalog' format.  Matches to existing Proper motion data when available.
- Design, observation, processing of 'calibration/standard'
- plates with stars of known [Fe/H], RV, log g, etc.

## Enhanced Goals:

- Imaging processing:  Ability to process imaging in regions of
- high stellar density (|b| < 10 deg), producing accurate catalogs
- stellar magnitudes and positions in these regions.
- Calibration: Use crossing scans or other techniques to
- improve photometry from ~2% RMS to ~1% with fewer outliers.
- Spectroscopy: Incorporate parameter (i.e. [Fe/H]) estimation
- into pipeline processing.
- Database:  Insert Imaging catalogs and spectra w/ all
- parameters (i.e. PPM matches, Rvs),
- into indexed database (i.e. CAS-style) in addition to DAS style
- flat field access.

## To Do List:

- Great interest has been expressed by current and
- new partners in SEGUE and the other SDSS-II
- science projects.
- Note that we are currently effort limited, and need to
- organize a team to handle development and operations
- as well as science analysis aspects of SEGUE, and
- we hope and expect to draw resources from
- many of you.

## Development tasks (broad categories: target selection, imaging, spectro, 

- data processing, Q/A,
- calibration/standards, science analysis, database and distribution
-  [and, of course, documentation]):
- Target Selection tasks:
- Refine, verify SEGUE Target Selection algorithm in each of the
- 10 Stellar Categories (F turnoff, G dwarf, K giant, BHB/A, Low Metalicities)
- [There are at least projects for 10 people here!]:
- 		[Weight low-metal stars to bright mags < 18, improve K-giant
- efficiency from current 20%]
- Are we selecting the right stars enough stars in each category to
- do the science (trace halo streams or disk structure, explore metalicity
- history of the Milky Way or Chemical gradients in the Galaxy.
- Are we  selecting enough stars in each category to have sufficient statistics
- to do the science? [More F stars to trace streams?]
- Web link to target selection color/mag cuts and links to early SEGUE plates.
- (A more formal web page is coming)

- http://www-sdss.fnal.gov/yanny/seguets/

## Imaging:

-       Plan, obtain and reduce SEGUE imaging stripe
- 	data.
- 	Analyze photometric accuracy as f(stellar density).
- 	Update imaging pipeline to work at high density
- 		[i.e. stars-only 'DAOPHOT' mode]
- 	Analyze photometric accuracy as f(dust/variable sky).
- 	Update imaging pipeline to work in variable sky
-        background conditions (i.e. |b| ~0.
- Spectroscopy:
- Plan, obtain and process SEGUE plate pairs.
- 	Analyze RV accuracy as f(S/N), stellar color/type.
-       Update RV templates as needed to reach goals.
- [Do we have enough sky fibers?  New ELODIE templates to insert
- zeropoints, N best fit (now 12)]
-      Develop algorithms for [Fe/H], Teff, log g of stars
- 	as f(S/N), stellar type. [Expanded Lick indicies,
- continuum-subtracted spectra in blue, smoothing,
- unskysubtracted-sky spectra availability]
-      Incorporate algorithms into pipeline processing.

## Quality Assurance:

- 	During observing 2004-2008,
-  monitor imaging and spectra data as they occur. Within
- one month timescale for imaging (turn around for Target Selection),
- check tracking, photometric accuracy, S/N depth of images.
- Color magnitude diagrams.  Search for 'special regions to scan'
- i.e. if a new 'great stream appears'.
- Spot check spectra of each type vs. S/N estimates and science
- requirements.
- Calibration/Standards:
-   (IM) target and process 'PT' patches along SEGUE stripes for initial
- 2% rms calibration (in time for Target Selection).
-     scan crossing scans as needed to allow photometric ties of
- SEGUE 'constant l' stripes to each other and to SDSS imaging.
-     process crossing scan and other available photometric calib info.
- (SP)  Obtain samples of stars with known Rvs, Metals, log g,
- spectral types to calibrate algorithms for parameter estimation.
- i.e. plates on Globular and Open Clusters of known RV, [Fe/H].
- Match to USNO-B2.0 or other catalogs of known info proper motions.

## Databases/Data distribution/Documentation:

- 	Support initial catalogs and value-added information
-  as 'Flat Files' in SDSS 'DAS' format, with web sites
- 	Design/Modify 'indexed-database' design to include
- new parameters/information  (data model changes).
- 	Publish (in some form), TS algorithm, selection
- function, goals and science background.
- Science Analysis:
- 	Stellar Atmosphere modeling and parameter estimation is still a bit of a
- 'black art', we need your experts and expertise.  SEGUE has potential
- to revolutionize this field!!  Think Big!
- 	Work on the key project or some of the other
- '57' science projects with initial sample (~20,000 SEGUE
- stars already available in Aug/Sep 04) with intent
- to determine feasibility of the science.

## Papers:

- Metals in Sag stream
- Metals in Mono/Canis Major Stream
- Spectra of everything selection function, stellar spectral atlas
- SDSS DR2/DR3 selection function, target selection algorithm
- Metalicity Distribution in the MW (DR2 and beyond)
- The Lowest Metal Stars
- Techinques for measures stellar atmosphere
- parameters in large sample of R~2000 SDSS spectra.
- SEGUE Target Selection and early results.

## We are 'new' to the rich field

- of stellar kinematic
- and population analysis,  with
- implications for dark matter and
- galaxy history studies on the
- Galaxy easiest to observe.
- We need your help! [Meeting Oct 2]
- There are many opportunities to
- contribute, including student projects.

## Color-Magnitude (g-r,g) diagram for Strip 1260N

- Dual turnoffs,
- indicates
- stream(s?) at
- 10 and 20 kpc
- from the sun.

- Thick  Disk Fs

- Halo or stream(s)?

- Thin disk M stars

## SEGUE as of September 30, 2004

-   Black= completed stripe or plate pair

## WD

- A/BHB
- F Turnoff
- G III +V
- Low Metals
- K III
- K V
- M V
- AGB
- Cool Wds

- SEGUE currently has 10 categories,
- 	(we have openings for G dwarf specialists)

## G dwarf Radial Velocity histograms, by Magnitude (dist)

- -250     -200   -150    -100    -50    0     50 km/s

## Slide 20

## SEGUE  spectroscopic sample:

- Radial Velocities of populations
- of similar stars,
- Metalicity, Teff, log g determinations
- Kinematic, Chemical population
- studies of the Milky Way and halo

## Slide 22

## White Dwarf 

- White Dwarf

- Issues: ?

- N=25

## Cool White Dwarf Candidate

- Issues: Proper Motion > 30mas/yr

- N=10

## BHB Star,  probe outer halo, streams to 150 kpc

- Issues:  Are we getting essentially 'all' of these?

- N=125

## -400      -300     -200      -100     0        100 km/s

## F turnoff star, trace streams, halo, low [Fe/H] to 20kpc

- Issues: Do we need more faint Fs per plate for streams?
- What about P1 cut?

- N=150

## -400      -300     -200      -100     0        100 km/s

## G dwarf, largest SEGUE sample, probe  disk/inner halo 

- G dwarf, largest SEGUE sample, probe  disk/inner halo
- 1.5kpc to 8 kpc  distances, Stream Giants also here

- Issues: Giants vs. Dwarfs?  Color band ok?

- N=375

## -400      -300     -200      -100     0        100 km/s

## K Giants 

- K Giants

- Issues: Color cuts ok, selection efficiency still low?

- N=125

## K Giant:

- Narrower
- lines,
- features
- less deep.
- K dwarf
- Stronger
- features,
- broader
- lines.

## K dwarf , kinematics from match to USNO-B, +RV

- photometric parallax – probe  disks from 0.5 – 2 kpc

- Issues: Faint cutoff?
- USNO Match?  Disk Science ok?

- N=125

## Low metalicity candidate,  [Fe/H] = -2.6, g=15.8, g-r=0.47

- Pop III exploration,  gradients in inner/outer halo

- Issues: Wish to weight much more towards bright g<18.5

- N=150

## M dwarfs

- Issues: sub-dwarf alg, brown dwarf alg, PPM cut modify?
- How faint?

- N=50

## AGB candidate, Giants in Sagittarius/Monoceros streams?

- g = 16.5,g-r =1.12, u-g = 3.1,  RV= -72km/s d(AGB) = 18 kpc

- Issues: Efficiency, use only on Sag/Mon?  color cuts?

- N=10

## Issues: 

- Exposure times for GC plates?
- When will be ready to tackle Open Clusters?
- Peregrine's cross scan on open clusters for
- this Fall?
- Redo Hyades, M67?

- Globular Cluster Plates 1960-1962 (M15/M2)
- Open Cluster Plates
- M67, Hyades?  RV standards, go down stellar locus

## SEGUE is doing well with the

- grant of Fall season observing
- during the last full year of SDSS-I.
- This 2004 data is available to
- all SDSS participants  for analysis
- and papers.

## WD

- A/BHB
- F Turnoff
- G III +V
- Low Metals
- K III
- K V
- M V
- AGB
- Cool Wds

- Spectroscopic  targets selected to probe variety of distances from the sun
- from < 1 kpc to > 100 kpc, basically through a 'standard candle' color cut
- to select stars representative of each distance.

## Cool White Dwarf Candidate

## -43                       -37

- -31                        -25

- 1100S
- Binned
- 6x3deg

- l =50 deg
- at 4 b's.
- Possible
- stream
- present,
- but need
- to model
- spheroid.

- Photo
- in
- crowded
- fields
- as we
- pass thru
- |b| = 0
- plane,
- will be
- improved
- in SEGUE
- outyears.

## SEGUE footprint as of Sep 30, 2004

- Black= completed stripe/plate
- 29/400 plates 7% done.

## Slide 43

## K Giants 

- K Giants