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An innovative interpretation of X-ray data from a cluster of galaxies could help scientists fulfill a quest they have been on for decades: determining the nature of dark matter.

The finding involves a new explanation for a set of results made with NASA’s Chandra X-ray Observatory, ESA’s XMM-Newton and Hitomi, a Japanese-led X-ray telescope.

If confirmed with future observations, this may represent a major step forward in understanding the nature of the mysterious, invisible substance that makes up about 85% of matter in the universe.

“We expect that this result will either be hugely important or a total dud,” said Joseph Conlon of Oxford University who led the new study. “I don't think there is a halfway point when you are looking for answers to one of the biggest questions in science.”

The story of this work started in 2014 when a team of astronomers led by Esra Bulbul (Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.) found a spike of intensity at a very specific energy in Chandra and XMM-Newton observations of the hot gas in the Perseus galaxy cluster.

This spike, or emission line, is at an energy of 3.5 kiloelectron volts (keV). The intensity of the 3.5 keV emission line is very difficult if not impossible to explain in terms of previously observed or predicted features from astronomical objects, and therefore a dark matter origin was suggested.

Bulbul and colleagues also reported the existence of the 3.5 keV line in a study of 73 other galaxy clusters using XMM-Newton.

The plot of this dark matter tale thickened when only a week after Bulbul’s team submitted their paper a different group, led by Alexey Boyarsky of Leiden University in the Netherlands, reported evidence for an emission line at 3.5 keV in XMM-Newton observations of the galaxy M31 and the outskirts of the Perseus cluster, confirming the Bulbul et al. result.

However, these two results were controversial, with other astronomers later detecting the 3.5 keV line when observing other objects, and some failing to detect it.

The debate seemed to be resolved in 2016 when Hitomi especially designed to observe detailed features such as line emission in the X-ray spectra of cosmic sources, failed to detect the 3.5 keV line in the Perseus cluster.

“One might think that when Hitomi didn’t see the 3.5 keV line that we would have just thrown in the towel for this line of investigation,” said co-author Francesca Day, also from Oxford. “On the contrary, this is where, like in any good story, an interesting plot twist occurred.”

Conlon and colleagues noted that the Hitomi telescope had much fuzzier images than Chandra, so its data on the Perseus cluster are actually comprised of a mixture of the X-ray signals from two sources: a diffuse component of hot gas enveloping the large galaxy in the center of the cluster and X-ray emission from near the supermassive black hole in this galaxy.

The sharper vision of Chandra can separate the contribution from the two regions. Capitalizing on this, Bulbul et al. isolated the X-ray signal from the hot gas by removing point sources from their analysis, including X-rays from material near the supermassive black hole

In order to test whether this difference mattered, the Oxford team re-analyzed Chandra data from close to the black hole at the center of the Perseus cluster taken in 2009.

They found something surprising: evidence for a deficit rather than a surplus of X-rays at 3.5 keV.

This suggests that something in Perseus is absorbing X-rays at this exact energy. When the researchers simulated the Hitomi spectrum by adding this absorption line to the hot gas’ emission line seen with Chandra and XMM-Newton, they found no evidence in the summed spectrum for either absorption or emission of X-rays at 3.5 keV, consistent with the Hitomi observations.

The challenge is to explain this behavior: detecting absorption of X-ray light when observing the black hole and emission of X-ray light at the same energy when looking at the hot gas at larger angles away from the black hole.

In fact, such behavior is well known to astronomers who study stars and clouds of gas with optical telescopes. Light from a star surrounded by a cloud of gas often shows absorption lines produced when starlight of a specific energy is absorbed by atoms in the gas cloud.

The absorption kicks the atoms from a low to a high energy state. The atom quickly drops back to the low energy state with the emission of light of a specific energy, but the light is re-emitted in all directions, producing a net loss of light at the specific energy – an absorption line – in the observed spectrum of the star. In contrast, an observation of a cloud in a direction away from the star would detect only the re-emitted, or fluorescent light at a specific energy, which would show up as an emission line.

The Oxford team suggests in their report that dark matter particles may be like atoms in having two energy states separated by 3.5 keV. If so, it could be possible to observe an absorption line at 3.5 keV when observing at angles close to the direction of the black hole, and an emission line when looking at the cluster hot gas at large angles away from the black hole.

“This is not a simple picture to paint, but it’s possible that we’ve found a way to both explain the unusual X-ray signals coming from Perseus and uncover a hint about what dark matter actually is,” said co-author Nicholas Jennings, also of Oxford.

To write the next chapter of this story, astronomers will need further observations of the Perseus cluster and others like it.

For example, more data is needed to confirm the reality of the dip and to exclude a more mundane possibility, namely that we have a combination of an unexpected instrumental effect and a statistically unlikely dip in X-rays at an energy of 3.5 keV. Chandra, XMM-Newton and future X-ray missions will continue to observe clusters to address the dark matter mystery.

A paper describing these results was published in Physical Review D on Dec. 19. The other co-authors of the paper are Sven Krippendorf and Markus Rummel, both from Oxford. NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra's science and flight operations.

LAKEPORT, Calif. – The Northshore man who ran his pickup into a downtown Lakeport store on Christmas night made his first court appearance in the case this week.

Jason Kaluna Fugit, 46, of Nice, was arraigned in Lake County Superior Court on Wednesday, according to District Attorney Don Anderson.

Anderson said Fugit is charged with felony vandalism, burglary and reckless driving for crashing his truck into the front of the Campos Casual store on Monday night.

On the night of Fugit’s arrest, a judge gave a bail enhancement of $500,000 in the case. Anderson said that enhancement remains in place, with Fugit still in custody.

Fugit is due to return for appearance of counsel and plea entry at 8:15 a.m. Jan. 3. Anderson said Mitchell Hauptman was appointed as Fugit’s attorney.

Shortly before 7 p.m. Christmas night, Fugit drove his Chevy Silverado through the front of the Campos Casuals store, located at 344 N. Main St., as Lake County News has reported.

Lakeport Police Officer Tyler Trouette said he arrived to find Fugit standing in front of the store and his pickup in the back of the building. It had smashed not just through the glass entryway but through counters and merchandise displays.

Trouette said it appeared that Fugit had lined up his pickup and then accelerated through the front of the store. There were no signs of skid marks or attempts to brake.

Fugit’s criminal history includes his 2005 arrest for attempting to kill his grandmother, who he thought was conspiring with the government to commit treasonous acts.

He pleaded guilty to elder abuse and in 2008, was sentenced to eight years in prison but instead sent to the Napa State Hospital because he was found to have been insane at the time he tried to kill his grandmother.

Anderson said Fugit was released from the state mental hospital in the spring of 2015.

In recent months, Fugit has been regularly seen in downtown Lakeport with cardboard signs complaining of a government conspiracy to persecute him.

Since his 2015 release, Fugit has had no other criminal cases filed against him with the District Attorney’s Office, Anderson said.

Anderson said Fugit told authorities that he used to work for the Campos’ limousine service. Fugit said he thought the Camposes were part of a government conspiracy because he had been required to sign confidentiality forms to drive the limo.

Fugit also told investigators that the crash was an accident, but then claimed that his belief that the Camposes are part of a conspiracy was why he did it.

RheaBeth Campos, who along with husband Ron owns the store, said she recalled Fugit working for them a long time ago when they owned the limousine company. She said that was about 20 years ago.

Campos said Fugit worked for them, but “not for very long,” and only did a few limo runs, she said.

“I never knew who he was,” when he was standing on the corner more recently with his signs, she said.

Fugit did come into the store recently, bringing with him a written statement, Campos said.

The Campos’ son, James, who manages the store, took the statement and told his mother that it was page after page of ramblings.

RheaBeth Campos said her son threw the paper away, but after the crash he retrieved the statement from the dumpster to give to police.

Police originally estimated damage to the Campos Casuals building to be at least $100,000.

Campos said their insurance company will visit on Tuesday to give them an updated estimate.

In the meantime, the main damage already is cleaned up. “We’re quick on our feet,” said Campos.

However, there is still more to do, including additional cleaning, she said. They’ve also made themselves available to respond to requests for merchandise exchanges because of the Christmas shopping season.

As for the store’s future, it will return, Campos said, noting they will “absolutely” reopen.

Email Elizabeth Larson at This email address is being protected from spambots. You need JavaScript enabled to view it.. Follow her on Twitter, @ERLarson, or Lake County News, @LakeCoNews.

UPPER LAKE, Calif. – A pilot escaped serious injury in an airplane crash near Upper Lake early Thursday.

The Federal Aviation Administration reported that the crash occurred at around 12 a.m. on Thursday at the Gravelly Valley Airport.

The plane involved was a single-engine two-seat Aeropro Eurofox, manufactured in 2005 and registered to a West Sacramento owner, according to FAA records.

The brief FAA report on the crash said that the aircraft landed hard on Gravelly Valley Airport’s Runway 33.

The pilot reported the aircraft was damaged, however, the FAA said the extent of damage to the plane was unknown at the time of its report.

No injuries were reported.

Northshore Fire Protection District units responded to the crash but were cleared to leave by the FAA shortly before 1:15 a.m. Thursday, according to reports from the scene.

Firefighters reported over the air that, at that point, the damaged aircraft was in the middle of the airstrip, where it was expected to remain for a few days until the pilot moved it.

Email Elizabeth Larson at This email address is being protected from spambots. You need JavaScript enabled to view it.. Follow her on Twitter, @ERLarson, or Lake County News, @LakeCoNews.

LAKE COUNTY, Calif. – The California Highway Patrol’s Clear Lake Area office will conduct a driving under the influence and driver’s license safety checkpoint on Saturday, Dec. 30.

The CHP said the checkpoint will happen at a location somewhere within the unincorporated area of Lake County.

The agency said its goal is to ensure the safe passage of each and every motorist by targeting roads where there is a high frequency of intoxicated or unlicensed drivers.

The CHP said a sobriety/driver’s license checkpoint is a proven effective tool for achieving this goal and is designed to augment existing patrol operations.

Vehicles will be checked for drivers who are under the influence of alcohol or drugs, or driving unlicensed, the CHP said.

The objective is to send a clear message to those individuals who consider driving and mixing alcohol or drugs, or driving when unlicensed, that they will be caught and their vehicle towed away.

Funding for this program was provided from a grant from the California Office of Traffic Safety through the National Highway Traffic Safety Administration.

NORTH COAST, Calif. – Mendocino County authorities arrested a Clearlake man after finding him in possession of a stolen vehicle and mail that was stolen from a number of Ukiah residences.

Javier Mejia Valencia, 29, was arrested late Wednesday night, according to Sgt. Matthew Kendall of the Mendocino County Sheriff’s Office.

Kendall said that in preparation for the holiday season, the Mendocino County Sheriff’s Office began working with local citizens on an intensive surveillance program, targeting thefts from rural mail boxes.

As a result of that effort, at about 11:15 p.m. Wednesday the Mendocino County Sheriff's Office became aware that a subject began taking mail and packages from the Oak Knoll Road area, Kendall said.

Responding deputies spotted the subject and he suddenly fled, speeding away in a vehicle as he observed an approaching patrol vehicle. Kendall said deputies pursued the vehicle to the area of Poulos Court where the driver jumped from the vehicle as it was still in motion.

Kendall said the vehicle the male subject was driving hit a parked car while the fleeing driver began running through the yards of residences in the area, attempting to elude capture.

Officers from the Ukiah Police Department, responding to assist the deputies in this pursuit, contacted Mejia Valencia exiting the rear of a residence on Tedford Avenue, Kendall said.

Mejia Valencia told officers he lived in the house and had simply walked outside to see what was going on. However, Kendall said officers noticed Mejia Valencia was sweating and had mud and debris from trees on his head and clothing.

When officers asked Mejia Valencia his address, he could not provide the numbers or the street name, Kendall said.

Kendall said deputies found the vehicle was reported stolen out of Napa County. The license plates had been removed and paper dealer plates were attached to the vehicle.

The vehicle contained several pieces of stolen mail and packages from the Oak Knoll Road area. Also located in the vehicle was Mejia Valencia’s cellular telephone, Kendall said.

Kendall said Mejia Valencia is currently on probation after recently being released from state prison under the state prison realignment.

Mejia Valencia was booked into the Mendocino County Jail on charges of mail theft, grand theft, possession of stolen property, reckless evasion and violation of probation. Kendall said Mejia Valencia is being held without bail.

Lake County District Attorney Don Anderson said Mejia Valencia has a history of spousal battery cases as well as other vehicle theft cases, including a November case in which he was reported to have stolen a car out of Santa Rosa.

LAKE COUNTY, Calif. – AT&T is offering a $25,000 reward for information leading to the arrest and conviction of those responsible for the theft of catalytic converters from company vehicles parked at field operating centers in parts of California and Nevada.

Thieves are removing and stealing the converters, thereby reducing the number of vehicles available to respond to service issues, the company said.

Since mid-November, there have been 12 separate incidents of catalytic converter thefts from AT&T vehicles in the following areas: Reno, Nev.; and the California cities of Redding, Merced, Auburn, Hanford, Clearlake, Santa Cruz, Santa Rosa, Bakersfield, Placerville, Simi Valley and Yuba City.

“AT&T takes this matter very seriously,” said Mark McDonald, director network services, in Northern California, AT&T. “We’re hoping the reward will motivate people in the affected areas to be more alert and to pay close attention to any suspicious activity near AT&T work centers. We are cooperating with law enforcement to make sure those responsible are apprehended and prosecuted.”

AT&T urges anyone with information on these crimes to call 1-800-807-4205 to begin the investigation process and possibly claim the reward.

Citizens should contact local law enforcement immediately if they observe anyone without AT&T branded apparel in or near AT&T work centers after business hours.

Only one reward will be given per person who calls in a tip that leads to an arrest and conviction. Individuals cannot receive additional reward money for multiple tips or convictions.