Question: Who was the founding lead guitarist in the band whose single was used with "Bridge over Troubled Water" to create the charity single "A Bridge over You"?

full_context: Document 1: Midnight (Coldplay song): "Midnight" is a song by British rock band Coldplay for their sixth studio album, "Ghost Stories" (2014). It was written and produced by band members Guy Berryman, Jonny Buckland, Will Champion and Chris Martin, with production assistance from Paul Epworth, Daniel Green, and Rik Simpson, and co-production from Jon Hopkins. A music video for the "Ghost Stories" track was released on 25 February 2014 as a teaser for the then-unannounced sixth studio album. A promotional "Midnight" 7-inch vinyl single was pressed by Parlophone for Record Store Day 2014. The single, featuring the track on a single side of the record, was released on 17 April 2014, becoming the second music release by the band in promotion of "Ghost Stories".
Document 2: New Zealand top 50 singles of 2015: This is a list of the top-selling singles in New Zealand for 2015 from the Official New Zealand Music Chart's end-of-year chart, compiled by Recorded Music NZ. English singer-songwriter Ed Sheeran, English soul singer Sam Smith, Canadian R&B singer The Weeknd and New Zealand band Six60 each had three songs in the chart. The chart was topped by Mark Ronson featuring Bruno Mars' song "Uptown Funk". As well as the three songs by Six60, the chart also had songs by New Zealand artists Avalanche City and Savage.
Document 3: Bridge over Troubled Water (song): "Bridge over Troubled Water" is a song by American music duo Simon & Garfunkel. Produced by the duo and Roy Halee, the song was released as the follow-up single to "The Boxer" in January 1970. The song is featured on their fifth studio album, "Bridge over Troubled Water" (1970). Composed by singer-songwriter Paul Simon, the song is performed on piano and carries the influence of gospel music. The original studio recording employs elements of Phil Spector's "Wall of Sound" technique using L.A. session musicians from the Wrecking Crew.
Document 4: Mylo Xyloto: Mylo Xyloto is the fifth studio album by British rock band Coldplay. It was first released on 19 October 2011, by EMI Music Japan, and in other countries beginning on 21 October by Parlophone; it was later released on 25 October in the United States, by Capitol Records. The band collaborated closely with acclaimed producer Brian Eno following their successful collaborations on "Viva la Vida or Death and All His Friends", the band's fourth studio album.
Document 5: Chris Martin: Christopher Anthony John Martin (born 2 March 1977) is an English singer, songwriter, musician, record producer and philanthropist. He is best known as the lead singer and co-founder of the British rock band Coldplay. Born in Whitestone, near Exeter in Devon, Martin went to University College London where he formed a rock band with Jonny Buckland in 1996 called Pectoralz, which was eventually renamed Coldplay in 1998.
Document 6: A Bridge over You: "A Bridge over You" is a charity single recorded and released independently by the Lewisham and Greenwich NHS Choir, the choir of the Lewisham and Greenwich NHS Trust located in south-east London. It is a mashup of "Bridge over Troubled Water" by Simon & Garfunkel and Coldplay's 2005 single "Fix You", with additional arrangement by the choir's conductor, Peter Mitchell. It reached number one on the UK Singles Chart at Christmas 2015.
Document 7: Across the Bridge of Hope: Across the Bridge of Hope is a compilation album created and recorded in support of victims of the Omagh bombings, by Tim Hegarty and Ross Graham. The album was released on July 13, 1999, by White Records. The album included various songs by Irish artists, as well as two poem recitations by actor Liam Neeson. The album draws its name from the second of these two poems, written by twelve-year-old Sean McLaughlin, who wrote it shortly before he was killed in the bombing.
Document 8: In Your Care: "In Your Care" is the second single released by singer-songwriter Tasmin Archer. It was released in early 1993 but failed to pick up as much airplay and media support as "Sleeping Satellite". "In Your Care" stalled at number 16 on the UK Singles Chart. The money made from this release was donated to the charity Child Line, just like the number-one single, "With a Little Help from My Friends"/"She's Leaving Home", by Wet Wet Wet & Billy Bragg.
Document 9: Band of Brothers (Only Men Aloud! album): Band of Brothers is the second studio album by the choir Only Men Aloud!. Unlike their self-titled debut, it featured several traditional Welsh songs, the album closing with a version of "Land of My Fathers". However, as on the first album, the choir also included covers of pop songs "Total Eclipse of the Heart", a duet with the original singer Bonnie Tyler, "Somebody to Love" with featured vocalist Kerry Ellis, and "Scarborough Fair".
Document 10: Richard Ashcroft: Richard Paul Ashcroft (born 11 September 1971) is an English singer and songwriter. He was the lead singer and occasional rhythm guitarist of the alternative rock band The Verve from their formation in 1990 until their original split in 1999. He became a successful solo artist in his own right, releasing three UK top three solo albums. The Verve reformed in 2007 but again broke up by summer 2009. Ashcroft then founded a new band, RPA & The United Nations of Sound, and released a new album on 19 July 2010. On 22 February 2016 Ashcroft announced his fourth solo album, "These People", set for release 20 May 2016. Chris Martin of Coldplay has described Ashcroft as "the best singer in the world".
Document 11: Coldplay: Coldplay are a British rock band formed in 1996 by lead vocalist and keyboardist Chris Martin and lead guitarist Jonny Buckland at University College London (UCL). After they formed under the name Pectoralz, Guy Berryman joined the group as bassist and they changed their name to Starfish. Will Champion joined as drummer and backing vocalist, completing the lineup. Creative director Phil Harvey is often referred to as the fifth member by the band. The band renamed themselves "Coldplay" in 1998, before recording and releasing three EPs: "Safety" in 1998 and "Brothers & Sisters" and "The Blue Room" in 1999. "The Blue Room" was their first release on a major label, after signing to Parlophone.
Document 12: Foals (band): Foals are an English indie rock band from Oxford, England formed in 2005, consisting of lead vocalist and lead guitarist Yannis Philippakis, drummer and percussionist Jack Bevan, rhythm guitarist Jimmy Smith, bassist Walter Gervers, and keyboardist Edwin Congreave. Since the band's formation, their line-up has remained constant, except for the departure of former lead singer Andrew Mears.
Document 13: Blur discography: The discography of English alternative rock band Blur consists of eight studio albums, five live albums, five compilation albums, one remix album, two video albums, four extended plays, twenty-nine singles, eight promotional singles and thirty music videos. Formed in London in 1988, the group consists of singer/keyboardist Damon Albarn, guitarist/singer Graham Coxon, bassist Alex James and drummer Dave Rowntree. Three years later their debut release, the Madchester and shoegazing-tinged "Leisure" (1991), peaked at number seven on the UK Albums Chart. With "Modern Life Is Rubbish" (1993) inaugurated the Britpop phase of their career. Its multi-Platinum follow-ups "Parklife" (1994) and "The Great Escape" (1995) helped the band achieve mainstream popularity in Britain; every Blur studio album from "Parklife" onwards has topped the British charts.
Document 14: Over (Portishead song): "Over" is the second single of the album "Portishead" by the trip hop trio of the same name. It was #25 in the UK Charts at the time of its release. It has been used in numerous TV shows and movies.
Document 15: Radiohead: Radiohead are an English rock band from Abingdon, Oxfordshire, formed in 1985. The band consists of Thom Yorke (lead vocals, guitar, piano, keyboards), Jonny Greenwood (lead guitar, keyboards, other instruments), Ed O'Brien (guitar, backing vocals), Colin Greenwood (bass), and Phil Selway (drums, percussion, backing vocals). They have worked with producer Nigel Godrich and cover artist Stanley Donwood since 1994.
ground_truth: Jonny Buckland