HOP 0120

abstract of observational proposal

The balloon-borne telescope Sunrise will offer observations of the solar atmosphere with unprecedented spatial resolution. For this unique and singular opportunity we want to collect diversified additional data which cannot be obtained with the limited instrumentation onboard of Sunrise.
Sunrise will carry out imaging in different photospheric and lower chromospheric channels together with 2D-spectropolarimetric observations of a photospheric iron line (detailed scientific goals of Sunrise can be found on http://star.mpae.gwdg.de/Sunrise/project/index.html). In order to maximize the scientific relevance of Sunrise, additional spectroscopic and polarimetric information of the upper photosphere and the chromosphere is highly desirable.
The Hinode spacecraft with its unique capabilities of seeing free observations in the visible, extreme UV and X-ray wavelength region presents a most valuable completion of the Sunrise science goals. The wavelength coverage of SOT/SP will offer insight into the detailed magnetic structure of the photosphere, sampled in high spatial and temporal resolution by the IMaX instrument on board Sunrise. Additionally, it will offer a unique possibility for cross-calibrating
the Sunrise instruments. The BFI and NFI imaging instruments will ideally complement the high resolution images of the SUFI camera. Additionally, EIS and XRT will offer observations in wavelength regimes not covered by the Sunrise telescope.
The scientific aims and the thus desired targets to be observed will be scheduled on a ”Sunrise observation timeline”. Detailed information about this timeline, including observing procedures, pointing positions, image thumbnails, and requirements for co-observation facilities will be available during the Sunrise flight (most likely on a dedicated web page).
The science goals of the Sunrise mission are:
• Sunrise will allow observations of all manifestations of small-scale magnetic structure on the crucial spatial scale of 30 to 100 km and for sufficiently long periods of time to study its evolution. The Sunrise observations will considerably advance our understanding of astrophysical magneto-convection and the energy deposition into the upper atmosphere.
• Sunrise will provide simultaneous high-resolution observations of the chromospheric brightness
together with the photospheric magnetic field and velocity structure. This will allow
us to identify the dominating heating mechanism of the chromospheric network as well
as to determine the spatial distribution of hot and cool material in the chromosphere and
to clarify its association with the magnetic field structure.
• Sunrise is optimized for precise spectroscopic and polarimetric measurements providing
the evolution of the magnetic field vector and the properties of the solar plasma with
unprecedented resolution. This will enable us to study the structure and the life cycle
of the intense magnetic flux bundles as well as to determine wave modes and shock
propagation, so that the transport of mechanical energy to the upper atmosphere may be
quantitatively investigated.
• Sunrise observations will provide the crucial information regarding the evolution of magnetic flux and the primary processes of flux emergence, recycling, magnetic reconnection, and removal from the photosphere.
• The study of the dynamics and energetics of small-scale magnetic concentrations afforded by Sunrise probably is the only way to reveal the physics of global solar variability, both for the total (wavelength-integrated) irradiance variations and for the larger variations at short wavelengths affecting the Earths upper atmosphere.
• With Sunrise we will actually see the working of the photospheric energy sources for heating the chromospheric network and the corona.
The scientific instrumentation of Sunrise is optimized for high resolution studies of the photoshpere and lacks spectropolarimetry in chromospheric lines. The planned observations with Hinode will ideally complement the Sunrise measurements.

remarks

2 Time Period for Observations

We ask for Hinode support during the entire flight of the Sunrise balloon. The flight duration is estimated to be up to 5 days. The exact date of the flight is not known. The sunrise launch window opens on June 1 (earliest possible launch date) and closes on July 5 (latest possible launch date). During this period the procedure for the Sunrise flight is as follows (all times are MESZ = UTC +2h):
1. Day before launch, 14:00: Weather briefing, if predictions are good, ’go ahead’ for launch preparations.
2. Launch day, 01:00: start of payload launch preparations (instrument functional checkout, instrument roll-out infront of integration hall, mounting of solar panels, wind shields, antennas, ballast hoppers etc.).
3. Continous weather monitoring regarding surface and mid altitude winds throughout the night and early morning, 2 - 3 sounding balloon launches.
4. Launch day, 04:00: instrument switch-on in stand-by, instrument check-out.
5. Launch day, 05:00: roll-out to launch pad, antenna check-out.
6. Wait for optimum weather conditions.
7. L-2,5 hours: Roll-out of balloon film and helium filling.
! decision to launch.
8. Launch (unsually approx. 07:30-10:00).
9. L+2,5 hours: balloon is at float, instrument comissioning, telescope and LISS co-alignment,
pointing system parameter tuning.
10. L+ 5 hours: start of observations.
According to this procedure, the decision to launch Sunrise is taken between 05:00 and 07:30 local time (MESZ, UTC+2), corresponding to 12:00 and 14:30 JST (UTC+9). First scientific observations are expected not earlier than 5 hours after the launch (12:30 to 15:00 local time, 19:30 to 22:00 JST).
We are aware of the complexity in the operation of the Hinode spacecraft caused by this uncertainty in the exact flight time. We would gratefully acknowledge the support from the Hinode team to find a good solution how to cope with this problem.

3 Detailed Timeline for Hinode Operations
The Sunrise observations will follow a predefined timeline. The details of this timeline will be finished by end of March 2009. This timeline accurately defines the observing sequences for the Sunrise instruments. About 50% of the Sunrise observing programs ask for support from Hinode. Once the Sunrise timeline is finalized we will provide a detailed plan for the desired Hinode
operations.
In addition to this standard timeline the Sunrise timeline may (and will) switch to the so-called target of opportunity modes. This means that the Sunrise timeline may change according to the activity on the Sun, e.g., if a sunspot appears, the Sunrise timeline will be adjusted to observe this sunspot. We will also provide a list of desired Hinode operations for these target of opportunity modes. The short duration of the Sunrise flight makes it unavoidable to quickly adjust the Sunrise program to the solar conditions. We know that this is adding a huge amount of complexity for the Hinode operation. We therefore strongly ask for daily operation to allow for maximum overlap in observations between Sunrise and Hinode.
Once the timeline of Hinode is uploaded (and cannot be changed anymore), Sunrise will do its best to follow the program defined by the Hinode spacecraft.

4 Estimated Data Volume
The data volume for the Hinode observations can be estimated after the Sunrise timeline is finalized. We expect use up 100% of the Hinode data rate capacity. The expected daily Hinode coverage lies between 6 and 8 hours.

5 Required Hinode instruments

After finalizing the Sunrise timeline we will specify a detailed list of the requested Hinode instrumentation. We will also prioritize the instruments in order to cope with the maximum allowed data rate. The scientific observing programs defined by the Sunrise team ask for support of all Hinode telescopes (SOT, XRT and EIS).

I attach two documents:

(1) Hinode-Modes.pdf: This document is a first draft defining possible Hinode operations.
(2) Observing_Plan_240309.pdf:

This is the first draft of the "Sunrise Observing Plan" containing Sunrise modes and the timeline.

Note that both documents (1) and (2) are still draft versions. Once the Sunrise timeline is fixed and the Hinode support for Sunrise is granted we will finalize the Hinode observing modes in close collaboration with Hinode chief observers.

About 10 days ago Sunrise arrived at the launch facility near Kiruna, Sweden. On-site integration is going smoothly, we do not expect delays and are optimistic to have Sunrise ready for launch on June 1st, the first day of the 6-week launch window.

We hope for a positive evaluation of our HOP request. We are convinced that the unique capabilities of Hinode will greatly enhance the scientific output of the Sunrise balloon mission!

Sincerely,
Andreas Lagg