Question: What fictional universe is aired on the CW for The Flash?

Context paragraphs:
List of Arrowverse cast members: The Arrowverse is a shared fictional universe that is the setting of superhero television series airing on The CW, produced by DC Entertainment and based on characters that appear in DC Comics publications.  The shared universe includes three live-action television series, "Arrow", "The Flash", and "DC's Legends of Tomorrow", and one animated web series, "Vixen".  The universe is set to expand with further animated web series set in the Arrowverse, "Freedom Fighters: The Ray" and "Constantine", in 2017.

The Flash (2014 TV series): The Flash is an American television series developed by Greg Berlanti, Andrew Kreisberg and Geoff Johns, airing on The CW.  It is based on the DC Comics character Barry Allen / Flash, a costumed superhero crime-fighter with the power to move at superhuman speeds.  It is a spin-off from "Arrow", existing in the same fictional universe.  The series follows Allen, portrayed by Grant Gustin, a crime scene investigator who gains super-human speed, which he uses to fight criminals, including others who have also gained superhuman abilities.

The Flash (season 4): The fourth season of the American television series "The Flash", which is based on the DC Comics character Barry Allen / Flash, follows a crime scene investigator with superhuman speed who fights criminals, including others who have also gained superhuman abilities.  It is set in the Arrowverse, sharing continuity with the other television series of the universe, and is a spin-off of "Arrow".  The season is produced by Berlanti Productions, Warner Bros.  Television, and DC Entertainment, with Andrew Kreisberg and Todd Helbing serving as showrunners.

Vixen (web series): Vixen is an American animated web series from executive producers Greg Berlanti, Marc Guggenheim and Andrew Kreisberg, which debuted on August 25, 2015, on The CW's online streaming platform, CW Seed.  It is based on the DC Comics character Mari McCabe / Vixen, a costumed superhero crime-fighter with the power to mimic the abilities of any animal that has ever lived on Earth.  The series is set in the Arrowverse, the same fictional universe as "Arrow", "The Flash", and "Legends of Tomorrow".  In January 2016, the series was renewed for a second season, which premiered on October 13, 2016.

Bongy Westphall Universe: The Bongy Westphall Universe is a fictional universe of 44 related films released by Full Moon Entertainment.  Series creator Charles Band took inspiration from team up comics he read as a child.  The universe is named after the Tommy Westphall Universe and also the film Evil Bong which presents the largest crossover in the fictional universe.  The named was coined by film podcast Double Feature during their "Killapalooza" episode highlighting the Puppet Master franchise.

Freedom Fighters: The Ray: Freedom Fighters: The Ray is an upcoming American animated web series developed by Greg Berlanti and Marc Guggenheim.  It will debut in 2017 on The CW's online streaming platform, CW Seed and is based on DC Comics character Ray Terrill / The Ray, a reporter who gains light-based powers after being exposed to a genetic light bomb.  The series is set in the Arrowverse, the same fictional universe as "Arrow", "The Flash", and "Legends of Tomorrow", while also taking place on the alternate earth, Earth-X.

Arrowverse: The Arrowverse is a shared fictional universe that is centered on television series airing on The CW, developed by Greg Berlanti, Marc Guggenheim, Andrew Kreisberg, Phil Klemmer, and Geoff Johns, based on characters appearing in publications by DC Comics.  The shared universe, much like the DC Universe in comic books or the cinematic DC Extended Universe, was established by crossing over common plot elements, settings, cast, and characters.  The Arrowverse stars Stephen Amell as Oliver Queen / Green Arrow, Grant Gustin as Barry Allen / Flash, Megalyn Echikunwoke as Mari Jiwe McCabe / Vixen, with an ensemble cast leading "Legends of Tomorrow", including Arthur Darvill as Rip Hunter, Caity Lotz as Sara Lance / White Canary, Brandon Routh as Ray Palmer / Atom, Dominic Purcell as Mick Rory / Heat Wave, with Victor Garber and Franz Drameh as Martin Stein & Jefferson "Jax" Jackson / Firestorm.  Russell Tovey stars as Ray Terrill / The Ray.

List of Legends of Tomorrow episodes: "Legends of Tomorrow" is an American action-adventure television series developed by Greg Berlanti, Marc Guggenheim, Andrew Kreisberg and Phil Klemmer, who are also executive producers along with Sarah Schechter and Chris Fedak; Klemmer serves as showrunner.  The series airs on The CW and is a spin-off from "Arrow" and "The Flash", existing in the same fictional universe.

Legends of Tomorrow: DC's Legends of Tomorrow, or simply Legends of Tomorrow, is an American superhero action-adventure television series developed by Greg Berlanti, Marc Guggenheim, Andrew Kreisberg, and Phil Klemmer, who are also executive producers along with Sarah Schechter and Chris Fedak; Klemmer and Fedak serve as showrunners.  The series, based on the characters of DC Comics, airs on The CW and is a spin-off from "Arrow" and "The Flash", existing in the same fictional universe.  The series premiered on January 21, 2016.  In January 2017, The CW renewed the series for a third season, which is scheduled to debut on October 10, 2017.

List of The Flash episodes: "The Flash" is an American action television series developed by Greg Berlanti, Andrew Kreisberg, and Geoff Johns, airing on The CW.  It is based on the DC Comics character Barry Allen / Flash, a costumed crimefighter with the power to move at superhuman speeds.  It is a spin-off from "Arrow", existing in the same fictional universe.  The series follows Barry Allen, portrayed by Grant Gustin, a crime scene investigator who gains superhuman speed, which he uses to fight criminals, including others who have also gained superhuman abilities.  "The Flash" was renewed in March 2016 for a third season, which premiered on October 4, 2016.  On January 8, 2017, The CW renewed the series for a fourth season, which is scheduled to debut on October 10, 2017.  s of 23, 2017, episodes of "The Flash " have aired, concluding the first half of the  season.

Supporting paragraphs: The Flash (season 4) Arrowverse
Answer: Arrowverse