Current roles
I am an ESA/AURA Astronomer (Level III) at the Space Telescope Science Institute, working as an Instrument Scientist for the Hubble Space Telescope's Advanced Camera for Surveys (ACS).
- ACS Calibration Lead – overseeing the calibration program for ACS and ensuring the long‑term stability and scientific quality of the instrument.
- Principal Investigator of the ACS external CTE calibration program – leading the observational program used to monitor charge transfer efficiency (CTE) losses in ACS/WFC and develop the photometric correction model for point sources.
ACS/WFC CTE photometric correction
CTE losses in ACS/WFC cause measurable photometric biases that grow with time as the detector accumulates radiation damage. My work in this area focuses on the photometric correction model, which allows users to correct CTE‑induced flux losses in their ACS/WFC photometry. I also co-authored a study on the impact of CTE degradation on extended sources.
Instrument Science Reports
-
Chiaberge, M., et al. (2022), ACS ISR 2022-06:
ACS/WFC CTE photometric correction: improved model for bright point sources.
[PDF: isr2206.pdf ] -
Chiaberge, M., et al. (2025), ACS ISR 2025-02:
The Impact of Degraded Charge Transfer Efficiency on Extended Sources in ACS/WFC.
[PDF: isr2502.pdf ]
Documentation and tools
Full documentation, correction tables, and tools are available on the STScI ACS CTE photometric correction webpage:
stsci.edu – ACS/WFC Photometric CTE Corrections
Selected past assignments
Hubble operations and review activities
- Member of the Hubble Space Telescope Time Review Board, contributing to the assessment of observing proposals.
- Member of the Big Data Science Definition Team, helping define priorities for data‑intensive projects at STScI.
Servicing Mission 4 (SM4) and ACS recovery
- Lead of the ACS Servicing Mission 4 Early Release Observations team, defining and executing early science observations with the restored ACS after SM4.
- Lead of the STScI SM4 Functional Test team during SM4‑EVA3, responsible for verifying the performance of ACS following on‑orbit servicing operations.
- Member of the Servicing Mission Orbital Verification (SMOV) team, supporting post‑servicing commissioning and verification.
Focus areas
- ACS calibration strategy and implementation.
- CTE photometric correction model for ACS/WFC.
- Support for HST observing programs using ACS.
- Post‑servicing verification and early science planning.
Impact
These roles ensure that ACS continues to deliver high‑quality data to the astronomical community, with robust calibration, well‑understood systematics, and effective support for both large and small HST programs.