Pre-Eruptive Filament Structures Nandita Srivastava (MPAE), Sara F. Martin (Helio Research), Davina Innes (MPAE) Received October 28, 1999 Scientic objective: The goal of this campaign is to observe the pre-eruptive structure and mass motions in 1 to 3 filaments and their overlying coronal arcades. This study would help in forecasting the properties of interplanetary clouds associated with CMEs and eruptive filaments, which are important with regard to Space Weather. Observing period: Nov 3-10, 1999 Method: We will identify one or more long quiescent filaments present on the disk of the sun during the observing period and will assign priorities to them as targets. Below we outline the observations as will be taken by various instruments. Proposed Observations from different instruments: (1) Helio Research - The H-alpha instrument will provide high-spatial resolution observations of the filaments/prominences covering a field of view ofApprox. 7 X 7 arc-min with a CCD camera providing an array of 1024 x1024 x12 bi pixels. The wavelengths will be both centerline and Doppler observations within the range of +1.5A to -1.5A. The rate of image acquistion will be 1/minute TO 1/4 minutes depending on the state of activity of the selected filaments or prominences. Observing time: 15:00 -22:00 UT (2) BBSO - Also high spatial and temporal observations of the same filaments in the red wing, blue wing and centerline H-alpha. BBSO will provide fewer wavelengths (MAX. of 3) but at higher cadence per wavelength than is planned at Helio Research. The field of view is smaller, approx. 5 X 5 ARC MIN. The exact choice of wavelengths will depend upon the target chosen. Observing time: 15:00 -22:00 UT (3) HASTA -H-alpha solar telecope for Argentina (German-Argentinean project) The H-alpha solar telescope at EL Leoncito in Argentina will take observations of the full disk of the sun every 2-3 minutes which will cover the activity on the sun. The H-alpha filter also has a tunable range of 1 A and will take one set of images at +0.5 and -0.5 A every 20 minutes. Observing Time: 11:30 -20:00 UT (4) MICA-Mirror coronagraph for Argentina (German-Argentinean project) The observations by MICA in Fe XIV green line will be taken at an average rate of an online image every 30 seconds- 90 seconds depending upon the sequence of continuum and flats in between.This instrument will be able to record the CMEs in the inner corona if associated with eruptive prominences on the limb, and will be extremely useful as LASCO-C1 is not operational now in order to study the initiation of the CME, in the lower corona. Observing Time: 11:30-20:00 UT (5) LASCO/EIT: LASCO -C2 and C3 coronagraphs will record the CMEs if there are any associated with filaments or prominences which erupt during our observing runin white light. The rate of images are 1/20 min and 1/30 min respectively. EIT will make regular observations in Fe XII 195 A line at 1 frame/12 min. And in other wavelengths (171, 284, 304 A) at 1:00, 7:00, 13:00 and 19:00 UT. Observing time: Continuous (6) CDS: Will observe the target filament in four wavelengths i.e. He I 584.33 , O V 629.73 A, Mg X 624.94 A, Fe XVI 360.76 A with a field of view of 8x4 arc-minute and 10sec exposure at 32 minute cadence. Observing Time: 16:00 -21:00 UT Contact Persons: Nandita Srivastava (MPAE) Sara F. Martin (Helio Research) Davina Innes (MPAE)