Dust Seeding Molecules in a Massive Protostar -- Detection of TiO in Orion Source I

@misc{zhang2026dust,
  title = {{Dust Seeding Molecules in a Massive Protostar -- Detection of TiO in Orion Source I}},
  author = {Ziwei E. Zhang and Nami Sakai and Marcelino Agundez and Linda Podio and Claudio Codella and Tomoya Hirota and Adam Ginsburg and Brett McGuire and Nadia M. Murillo and Yuki Okoda and Yoko Oya and Giovanni Sabatini and Aki Takigawa and Kei E. I. Tanaka and Yichen Zhang and Qiuyi Luo and Yu Cheng and Izaskun Jimenez-Serra and Shogo Tachibana},
  howpublished = {arXiv},
  year = {2026},
  month = sep,
  doi = {10.48550/arxiv.2608.01505},
  eprint = {2608.01505},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2608.01505},
}

TY  - UNPB
TI  - Dust Seeding Molecules in a Massive Protostar -- Detection of TiO in Orion Source I
AU  - Ziwei E. Zhang
AU  - Nami Sakai
AU  - Marcelino Agundez
AU  - Linda Podio
AU  - Claudio Codella
AU  - Tomoya Hirota
AU  - Adam Ginsburg
AU  - Brett McGuire
AU  - Nadia M. Murillo
AU  - Yuki Okoda
AU  - Yoko Oya
AU  - Giovanni Sabatini
AU  - Aki Takigawa
AU  - Kei E. I. Tanaka
AU  - Yichen Zhang
AU  - Qiuyi Luo
AU  - Yu Cheng
AU  - Izaskun Jimenez-Serra
AU  - Shogo Tachibana
PY  - 2026
DA  - 2026/09/16
PB  - arXiv
DO  - 10.48550/arxiv.2608.01505
UR  - https://arxiv.org/abs/2608.01505
AB  - We report the first detection of TiO in star-forming regions based on Atacama Large Millimeter/submillimeter Array observations of Orion Source I, a well-characterized massive protostar. Multiple rotational transitions are identified, with emission spatially resolved within ∼ 50 au, showing a compact distribution with a velocity structure consistent with the base of a rotating outflow. The spatial and velocity distributions of TiO are consistent with those of AlO, with both species being key dust seeding refractory molecules. The column density of TiO is derived to be (3.0 ± 0.4)×10^15 cm^−2, corresponding to X_TiO/SiO ∼ 12.8 ± 1.7 ×10^−3, higher than CI chondrites and indicative of efficient dust-to-gas conversion near the protostar. The detection of TiO, a key dust seeding species, offers important constraints on refractory chemistry and the formation environments of primitive minerals, linking astrochemical processes in protostellar systems to the earliest stages of Solar System material formation.
ER  -