Excitement was generated in the cosmic research community because of the gamma-ray observations recorded by the Large High Altitude Air Shower Observatory, LHAASO in Tibet, of energies more than one petaelectronvolt. The existence of cosmic accelerators much beyond the Earthly particle accelerators has been hinted. However, it has further raised questions over the exactness of such measurements when interference from thunderstorms is deemed a major problem.
Role of Thunderstorms in Enriching Particle Showers
Research Results
A study led by the director of the Aragats Cosmic Ray Research Station, Ashot Chilingarian, and Mary Zazyan from the Yerevan Physics Institute has brought to attention the role of thunderstorms in showers of atmospheric particles. Their research, published in The Astrophysical Journal Letters, shows how electric fields in thunderstorms intensify particle showers, thereby overestimating the gamma ray energy levels detected by observatories such as LHAASO.
The researchers proposed a model showing that thunderstorms could amplify subatomic particles to levels that mimic ultra-high-energy gamma rays. They highlighted the absence of disclosed weather-related data for LHAASO’s detections, urging greater transparency in correlating atmospheric conditions with gamma ray events.
LHAASO’s Response to the Concerns
Monitoring Practices
Zhen Cao, LHAASO spokesperson, explained that his team monitors the weather using antennas that measure atmospheric electric fields. He also pointed out that thunderstorms are relatively rare in the mountainous regions of Tibet, so interference is unlikely.Rejection of Strong Correlation
Cao dismissed any direct relationship between thunderstorms and the gamma ray detections, noting that no apparent pattern has been identified. However, the lack of publicly shared data on atmospheric conditions has left room for speculation.
Comparisons with Other Observatories
High Altitude Water Cherenkov Observatory (HAWC)
The HAWC Observatory in Mexico has employed strong interference-minimizing measures against thunderstorms. According to Los Alamos National Laboratory researcher Kelly Malone, HAWC continuously monitors atmospheric electric fields to identify anomalies. Malone said that gamma ray events recorded at HAWC are found to be evenly distributed in time and therefore have a minimal effect from weather conditions.
Expert Recommendations
Interpret with Caution
Leading scientists, such as German DESY laboratory’s head Johannes Knapp, promote caution and verification of ultra-high-energy gamma ray observations. Even though this interference due to the atmosphere has not yet been confirmed, it will be important to scrutinize the data and methods even more closely.
Call for Transparency
Experts have also demanded higher transparency in publishing data on correlations between weather conditions and observed gamma ray events. This openness could help to remove some of the uncertainties and strengthen the confidence in the findings.
Cosmic Studies Implications
Gamma-ray detection above one PeV may mark a threshold to understanding cosmic accelerators. However, the protracted debate about the role of thunderstorms emphasizes the complexity of carrying out high-energy research phenomena in Earth’s atmosphere, which is still being continuously done. Advanced monitoring integration with transparent data sharing at each step will be instrumental in ensuring the reliability of such groundbreaking discoveries.
